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2G Running lean and low vacuum after warming up weird symptoms.

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
So if you check my previous threads I had completely tore down my motor looking for an overheating issue which has been resolved. In the process I did a complete rebuild including new piston rings, valve job, new rods, new main/rod bearings & head/block shaved thinking I had a leaky head gasket which obviously wasn't the case. I did compensate with a thicker head gasket as instructed by the machine shop to do so as to not change the compression too much.

Now I've finally got the car running but when it does warm up I'm getting a lean condition 16.7 on the wide band fluctuating between normal when gas is slightly pressed and released then back to lean idling with around 10lbs of vacuum super low. I know even with 272 cams @ 1,000 rpm it shouldn't be that low.

Needless to say the car is not driving well, it even wants to shut down at certain times. Could this be due to a leaky exhaust system? I'm thinking if I have any vacuum leaks they are very minimal due to the fact that I replaced every hose with HPS hoses and steel braided lines.

Is it possible that an old intercooler or pipe coupler could be the culprit? The symptoms are leading me to believe otherwise.

This all started when I drove into a puddle a little deeper than I thought wet the whole inside of the engine, immediately the car shut off and wouldn't run after replacing the O2 sensor in the front and the MAF sensor. I was able to get it running but that's when it started running lean. I figured the engine rebuild would hopefully fix it cause my rings were pretty bad but now that I got everything back together and it's still doing the same thing especially while cruising if I'm around 3,000 rpm and hit the gas to the floor it goes dead lean till the turbo starts to spool up around 4500 rpm then it goes into the rich.

Also feels like it's almost going to misfire at idle. I did pull the ECU and had it tested, Supposedly it checked out fine last year when it happened. I took the ECU out and physically examined the board last week. I couldn't see anything burnt or any leaking caps I'm no ECU guy by any means, shouldn't I see/smell if there was any issues

Could this be a bad ground somewhere?

Where should I start testing? I'm thinking my leaky flex pipe needs to be fixed, if it is leaking, first just to rule that out because my O2 and wideband are located after it. For some stupid reason I guess 15 yrs ago when I had the exhaust done I wasn't thinking of that one LOL.

Anything you guys can think of to help me that'd be great. This is not easy for me, I am an amputee missing my leg doing all this work in a prosthetic LOL. Lots of time and money put into this thing for it to just sit in my drive way. It's killing me 🤣🤣😊 just trying to figure out why my ECU wouldn't tell the injectors to work more if it's seeing a lean condition & get better driveablity.

As of now when it warms up it drives like crap. Compression was exactly where it was last time I had to rebuild. Yes, a bit low, but I also have bigger cams with the head and block shaved. I'm guessing that could be a contributing factor. My starter cranking seriously slow which is why I was thinking a ground problem BTW, but even with the slow starter the compression was 112.5 exactly in each cylinder. The rings were gapped for higher horsepower according to Wiseco's specs. As far as I've been told the more important thing is that all the cylinders are within 10% of each other which 112.5 every cylinder I'd say that's dead on no?

Thank you in advance for any input guys!! Also, I am running the Greddy emanage or I'd offer to post logs. I know most people don't mess with those anymore but if someone can read a log for me plz feel free to message me LOL 😊. I'm praying it's not some loose wire somewhere from yrs ago. I know if certain things are working then the car should be running ok.

Any diagnostic information would really help 👍🏼. I already tested the injectors with a noid light they're all working normally. Also tested crank and cam sensors, they checked out perfectly. Water temp sensor is working properly according to my logs. I didn't see any dips in fuel pressure while it's running lean but I am going to rewire the fuel pump just to also rule that out.

I'm hoping Steve sees this one 🤣 as a lot of his info has helped me tremendously in the past 👍🏼👍🏼
 
Last edited by a moderator:

steve

DSM Wiseman
14,998
1,799
Feb 3, 2002
Boulder, Colorado
I saw it but I can't read it. :(

My old brain can't parse big blocks of text anymore and it's getting close to bedtime so I'm not going to edit it tonight so I can read it.

Maybe you can do that for me and I'll look at it in the morning....
 

steve

DSM Wiseman
14,998
1,799
Feb 3, 2002
Boulder, Colorado
Ok, now I can kind of read it.

If I'm following this correctly you ran the car into a puddle, got the engine bay all wet but didn't go so deep as to hydrolock it.

After, you had over heating issues and in the process of tracking that down to a blockage in feed to the water pump, but wound up rebuilding the engine several times trying to find the cause. You had problems with the spark plug order and found that. Now the car is running but badly.

You seem to have several new issues:
Low Compression
Low Idle Vacuum
Lean AFR's
Leaking Exhaust
Slow Starter

A couple of questions, I expect others will have more:
Who did the timing belt last? Have you checked to make sure it's timed correctly.
Why did you choose to go with solid lash adjusters. Who adjusted them?
Have you run a leakdown test on each cylindar?
Have you tested the intake for any vacuum/boost leaks? What PSI and how long did it hold the pressure after you stopped filling it?
Do you have both a narrowband and wideband O2 sensor? Why is the narrowband installed after the flex section and not right after the turbo?
Where is your battery located, how big is it, and where do the grounds run?

That should give you a few things to check. Please be concise in your reply.

I took the ECU out and physically examined the board last week. I couldn't see anything burnt or any leaking caps I'm no ECU guy by any means, shouldn't I see/smell if there was any issues

Almost forgot, No. There are plenty of problems that you can't see. Only the most gross problems like parts burning up due to shorts or capacitors leaking are plainly visible. For now, if you seeing reasonable sensor data from the emanage the ECU isn't high on the suspect list.
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
I saw it but I can't read it. :(

My old brain can't parse big blocks of text anymore and it's getting close to bedtime so I'm not going to edit it tonight so I can read it.

Maybe you can do that for me and I'll look at it in the morning....
Thanks so much man I really appreciate it kinda hars to sum it up quickly it's very complicated issue & basically it's almost been a yr since being able to drive it so I can't remember everything I've touched but I'll explain the problems in order.

1st was the puddle of water I drove into that ruined a bunch of sensors maf, ect, o2 sensor upstream then I was finally able to get it to start and idle normal had the ecu checked at the time as well, but after getting warm the a/f is cycling between 14.7 and almost 17 staying more to the lean side. then while cruising I can maybe put about 25% throttle anything over that and it goes dead lean until the turbo starts to spool then it shoots into rich as it should.


the car also is also still running hotter than normal, which is leading me to believe the timing or some other factor is playing a part as well. also very weird acceleration almost like the computer is trying to hard to read what's going on from the sensors.

I literally rebuilt the whole motor because of this problem thinking I had bad rings or something of that nature being the vacuum is so low at idle around 10lbs if that at times only once warm first 5-10 mins or so she acts normal. possibly have a flex pipe leak pre o2 & wideband but I don't think this is the cause for the symptoms I'm getting. I already confirmed the o2 is cycling according to my gauges I have not yet checked to see if the ect sensor is matching my aem temp gauge but it's pretty much new could a bad downstream o2 cause the lean condition? from what I've read that's a no.

I don't even know where to start at this point already tested fuel injectors w ohm meter checked out perfect ran the noid light all are firing, crank and cam sensors are working normally brand new I'm stumped...
 
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Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
Ok, now I can kind of read it.

If I'm following this correctly you ran the car into a puddle, got the engine bay all wet but didn't go so deep as to hydrolock it.

After, you had over heating issues and in the process of tracking that down to a blockage in feed to the water pump, but wound up rebuilding the engine several times trying to find the cause. You had problems with the spark plug order and found that. Now the car is running but badly.

You seem to have several new issues:
Low Compression
Low Idle Vacuum
Lean AFR's
Leaking Exhaust
Slow Starter

A couple of questions, I expect others will have more:
Who did the timing belt last? Have you checked to make sure it's timed correctly.
Why did you choose to go with solid lash adjusters. Who adjusted them?
Have you run a leakdown test on each cylindar?
Have you tested the intake for any vacuum/boost leaks? What PSI and how long did it hold the pressure after you stopped filling it?
Do you have both a narrowband and wideband O2 sensor? Why is the narrowband installed after the flex section and not right after the turbo?
Where is your battery located, how big is it, and where do the grounds run?

That should give you a few things to check. Please be concise in your reply.



Almost forgot, No. There are plenty of problems that you can't see. Only the most gross problems like parts burning up due to shorts or capacitors leaking are plainly visible. For now, if you seeing reasonable sensor data from the emanage the ECU isn't high on the suspect list.

Ok going to try and get all questions answered in order

1. I always do the timing myself which I've had plenty of experience doing about 50x literally all timing marks were perfect.

2. The solid lash adjusters were the most expensive ones so when I was a kid I figured most expensive = best LOL I was young man 🤣

3. The machine shop just did the head valves job and all plus pressure tested for leaks.

4. I tried doing the leak down to see if I was getting bubbles in the coolant but I've never done one before and every time I'd connect the air the motor would spin so I gave up I can try again if someone can explain exactly how.

5. Yes both narrow and wide band & yes another stupid kid idea to have them relocated after the flex pipe but something is telling me I my gut it's electrical unless the water seriously damaged the flex pipe and it's expanding to open a hole letting unmetered air out pre o2/wb

I'm praying this is the case but again my gut is telling me that's not it. If the sensors are reading lean wouldn't the ecu richen up the mixture correct?

6. Battery is in the trunk. It's a Optima red top specific for my car which I've never had a problem with the battery but it is possible my 15yr old ground could be going bad. It's connected to the spare tire bolt hole. I figured that should be a pretty good ground but I'm going to re ground it just to be sure with new cable.

Could the ground affect the ECU output to the injectors if it's not 100%?
 
Last edited by a moderator:

99dsmer4g63

Proven Member
171
85
Sep 20, 2022
Shippensburg, Pennsylvania
You need to start making paragraphs in your very long posts. Separate them accordingly. In Steve’s first reply he said this. You’ll also notice that your first post has been edited by a moderator and did what you should have already done.

If you want help go back through your posts and make them into paragraphs according to the information you are putting out. If not a moderator will spend their own time doing it instead anyways. Not too much to ask of you IMO.

-Daniel
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
You need to start making paragraphs in your very long posts. Separate them accordingly. In Steve’s first reply he said this. You’ll also notice that your first post has been edited by a moderator and did what you should have already done.

If you want help go back through your posts and make them into paragraphs according to the information you are putting out. If not a moderator will spend their own time doing it instead anyways. Not too much to ask of you IMO.

-Daniel
I'm sorry. I really haven't had much practice writing much, so I tried to do the best I could. How exactly should I word everything? I'm not sure how to fix what I've wrote. I'm sorry.
 
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99dsmer4g63

Proven Member
171
85
Sep 20, 2022
Shippensburg, Pennsylvania
If you look at your second post for instance. When you type 1. And then explain what you want to hit enter a couple times or make sure there is a bigger space between what you said in 1. and before you start 2.

There isn’t a problem with what your writing and trying to say it’s the not separating things apart from one to the next. As you can see I told what you wanted to know. I hit the enter button twice and continued onto my next topic.

You can also go back to your second post and do exactly what I’m asking by editing the comment. If not Steve spends more time fixing your post than trying to help you with your problems.

-Daniel
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
Look at what I did to your first post and compare that to your others.

Ahh ok I see. I'm sorry man, I'll try my best to fix it I'm really not good at writing at all.

If you look at your second post for instance. When you type 1. And then explain what you want to hit enter a couple times or make sure there is a bigger space between what you said in 1. and before you start 2.

There isn’t a problem with what your writing and trying to say it’s the not separating things apart from one to the next. As you can see I told what you wanted to know. I hit the enter button twice and continued onto my next topic.

You can also go back to your second post and do exactly what I’m asking by editing the comment. If not Steve spends more time fixing your post than trying to help you with your problems.

-Daniel

Ahh ok perfect, I think I fixed it. I'm really not good at writing I'm sry pls let me know if I did it correctly thank you!

😅
 
Last edited by a moderator:

steve

DSM Wiseman
14,998
1,799
Feb 3, 2002
Boulder, Colorado
Ok going to try and get all questions answered in order

1. I always do the timing myself which I've had plenty of experience doing about 50x literally all timing marks were perfect.

I asked because if the mechanical timing was off that could have caused both your low vacuum and low compression.

You feel it's 100%, so we'll move on.

2. The solid lash adjusters were the most expensive ones so when I was a kid I figured most expensive = best LOL I was young man 🤣

I asked about the Solid LA because they require proper adjustment to make sure they don't cause the valves to lag or leak. Just another thing that might be related to your low vacuum and low compression.

3. The machine shop just did the head valves job and all plus pressure tested for leaks.

That's great, but not what I was asking. There are lots of other things involved that can leak air and cause poor performance.

4. I tried doing the leak down to see if I was getting bubbles in the coolant but I've never done one before and every time I'd connect the air the motor would spin so I gave up I can try again if someone can explain exactly how.

Again not what I was asking but good to know. It's my understanding that cylinder leak down tests are don't at Bottom Dead Center to avoid the pistons moving and turning the crank. Besides checking if you have leakage into the coolant this test will indicate the general health and give indications if there is leakage how/where it's leaking from. This still relates to vacuum and compression problems.

5. Yes both narrow and wide band & yes another stupid kid idea to have them relocated after the flex pipe but something is telling me I my gut it's electrical unless the water seriously damaged the flex pipe and it's expanding to open a hole letting unmetered air out pre o2/wb

I'm praying this is the case but again my gut is telling me that's not it. If the sensors are reading lean wouldn't the ecu richen up the mixture correct?

You may have damaged both sensors by soaking them as well as the electronics connected to them. The problem with holes in front of them is that the exhaust pulses will suck fresh air in, not that exhaust will leak out. This can cause the ECU to not enter closed loop and for your WB to report incorrect values.

A stock ECU can only do so much with fuel trims and I have no idea what if anything the emanage can do.

6. Battery is in the trunk. It's a Optima red top specific for my car which I've never had a problem with the battery but it is possible my 15yr old ground could be going bad. It's connected to the spare tire bolt hole. I figured that should be a pretty good ground but I'm going to re ground it just to be sure with new cable.

Could the ground affect the ECU output to the injectors if it's not 100%?

Trunk mounted batterys have all sorts of failure modes. Both the power cables and the ground cables need to be large enough to carry the current the starters use. When you size those cables you have to take the to and from distance into account. Wires that are too small or have connections that aren't clean and tight can limit the current and cause slow starter problems. But there are other things that can also do so.

If the injectors are pulsing they are likely getting a good enough ground signal from the ECU but may not be 100% up to spec.
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida

I asked because if the mechanical timing was off that could have caused both your low vacuum and low compression.

You feel it's 100%, so we'll move on.



I asked about the Solid LA because they require proper adjustment to make sure they don't cause the valves to lag or leak. Just another thing that might be related to your low vacuum and low compression.



That's great, but not what I was asking. There are lots of other things involved that can leak air and cause poor performance.



Again not what I was asking but good to know. It's my understanding that cylinder leak down tests are don't at Bottom Dead Center to avoid the pistons moving and turning the crank. Besides checking if you have leakage into the coolant this test will indicate the general health and give indications if there is leakage how/where it's leaking from. This still relates to vacuum and compression problems.



You may have damaged both sensors by soaking them as well as the electronics connected to them. The problem with holes in front of them is that the exhaust pulses will suck fresh air in, not that exhaust will leak out. This can cause the ECU to not enter closed loop and for your WB to report incorrect values.

A stock ECU can only do so much with fuel trims and I have no idea what if anything the emanage can do.



Trunk mounted batterys have all sorts of failure modes. Both the power cables and the ground cables need to be large enough to carry the current the starters use. When you size those cables you have to take the to and from distance into account. Wires that are too small or have connections that aren't clean and tight can limit the current and cause slow starter problems. But there are other things that can also do so.

If the injectors are pulsing they are likely getting a good enough ground signal from the ECU but may not be 100% up to spec.
thank you so much for helping, im going to tear into it tomorrow. im going to try to go in order from our last conversation hopefully ill write everything correctly so you wont have to edit so much.


the only way i see the timing being off would possibly be from shaving the head and block which i tried to compensate like i said previously by getting a thicker h.g. and as far as i can tell the timing marks looked dead on to the naked eye. could the timing be off a bit and the timing marks still align well?


the lash adjusters im hoping the machine shop adjusted after doing the valve job. he also put vacuum with some type of machine to each cylinder which read 100% he said on the gauge he also left it connected to see if it would leak and no leaks in the head at least.

that will be the first thing im going to test tomorrow morning for any major vacuum leaks or maybe a intercooler coupler is torn/not tight. I was going to use the smoke method i seen on this forum with blowing into the vacuum lines with a cigar if thats the best method? seems fairly easy compared to the other methods ive seen.


and yes as you said previously the upstream o2 sensor and my wide band both got fried from the water along with the maf sensor and tem sensor i replaced before i could even get the car to run again which at that point being it still wasnt running correctly a/f ratio wise and feels like the timing is off i went ahead after that to have the ecu tested and it supposedly checked out fine no issues i also explained to the ecu repair guy that it only happens after the car warms up so hopefully thats not the issue.

I did not replace the knock sensor though if that could be potentially a 2nd issue?


can the downstream o2 sensor possibly be bad as well causing the lean condition after the car warms up?from what ppl say here the downstream only checks to make sure the cat is working properly is this true? should i just change it anyway its about 20 yrs old?


also if i were to get a log and post a video of all the values the emanage can log would you be able to get a better idea of whats going on? i know it gives injector readings, maf, temp sens, knock and a few others.


that will be on the list of things ill be looking into first tomorrow morning checking the bettery ground. and engine grounds along with a few other things before i even test drive it again.


1.wrap the flex pipe with exhaust wrap to see if a/f ratios change even slightly if there were to be a hole there somewhere being the location of the o2 sensor being post flex pipe and the flex pipe looks in bad condition. does a lean condition cause timing to be pulled by the ecu?


2.test for vacuum leaks hopefully the cause of the low vacuum via smoke method if suggested? btw vacuum is only low after the car gets really warmed up at least 3-5 mins before i see it dropping after cold start.


3.re wiring fans due to them causing a misfire when i turned them on via switch. which is another reason i was thinking bad ground both fans are ran to relays to accessory power so not sure why else a misfire would occur other than not enough current for the ecu to work properly.


4.re ground battery which im hoping will possibly fix some thing as well being like i said previously the starter is super slow idk if that could also affect injector output which im not ruling out unless you guys dont think so?..

Test drive... what do you guys think I'm sorry for the long post but this car is literally like my 3rd child LOL thanks guys for any input.
 

chrysler kid

20+ Year Contributor
2,600
571
Dec 20, 2002
Mckinney, Texas
What do you mean? You havent tried anything he suggested to do in order to try to fix the car

You can ask a million questions and write a million guesses, but its not a math equation of guessing

Engines need air fuel and spark to run. Go down the list and verify everything is working

To run properly they need to suck bang and blow. Verify vacuum with no leaks, verify spark, verify compression


I mean you also have aftermarket camshafts and no tune so im sure that is another reason why it runs like crap

Compression test the motor (112.5 is low, like at 100psi it might not run anymore)

If compression numbers are suspect conduct leak down test

verify there is no boost or vacuum leaks by performing a boost leak test by pressurizing the system

If boost leak test is good then test fuel pressure at the rail

If fuel pressure is good verify spark with a spark tester that plugs into the plug wire

If spark is good then verify ignition timing with a timing light

If timing is good then begin to trace and trouble shoot possible issues with ecu or wiring. Verify live data readings correlate to numbers they are suppose to be at

Its like youre trying to throw out an idea grenade and hope something hits us. For all we know theres a rat eating your wires under the intake manifold. You have to get your trouble shooting in an order. Theres not one sensor thats just going to randomly get replaced and the car runs better.
 
Last edited by a moderator:

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
What do you mean? You havent tried anything he suggested to do in order to try to fix the car

You can ask a million questions and write a million guesses, but its not a math equation of guessing

Engines need air fuel and spark to run. Go down the list and verify everything is working

To run properly they need to suck bang and blow. Verify vacuum with no leaks, verify spark, verify compression


I mean you also have aftermarket camshafts and no tune so im sure that is another reason why it runs like crap

Compression test the motor (112.5 is low, like at 100psi it might not run anymore)

If compression numbers are suspect conduct leak down test

verify there is no boost or vacuum leaks by performing a boost leak test by pressurizing the system

If boost leak test is good then test fuel pressure at the rail

If fuel pressure is good verify spark with a spark tester that plugs into the plug wire

If spark is good then verify ignition timing with a timing light

If timing is good then begin to trace and trouble shoot possible issues with ecu or wiring. Verify live data readings correlate to numbers they are suppose to be at

Its like youre trying to throw out an idea grenade and hope something hits us. For all we know theres a rat eating your wires under the intake manifold. You have to get your trouble shooting in an order. Theres not one sensor thats just going to randomly get replaced and the car runs better.
Ahh ok, the car has been tuned on the dyno though and was running strong for yrs. that's why this is strange to me as well.

* it has consistent fuel pressure Even while the issue is happening when afrs are reading lean my fpr is set to 43psi

*I'm not thinking compression as a factor at all. it had 80psi each cylinder before I figured out it was the rings and it was running perfectly fine like that not even any smoke till I had the overheating issue and figured time to rebuild and got new rings.

*It's getting spark to all cylinders.in school they tought us to pull the plug and ground it some where safely and crank all 4 were firing it seemed with the same visual spark looked good 🤷 I'm going to do the boost leak test now is there a good method to do this?

Trust me I wish I had more knowledge of this car I would not be asking so many questions. if I would have finished my mechanic schooling I have a feeling I'd still be scratching my head on this one.

I have had various issues with the car but never like this it feels like it's a sensor the way the car drives its not smooth like it was either.

About to start I guess with fixing the flex pipe or putting a band aid on it at least by wrapping with exhaust wrap to cover any holes if any pre o2? That couldn't cause low vacuum though correct?
 

chrysler kid

20+ Year Contributor
2,600
571
Dec 20, 2002
Mckinney, Texas
Yeah or you can just unplug the front 02 sensor and see if it runs better after you unplug the connector

Can you take a good picture of your engine bay so I can observe all of the sensors and vacuum hoses.

Im visual and want to see what your engine bay looks like to see if there are any visual clues
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
Yeah or you can just unplug the front 02 sensor and see if it runs better after you unplug the connector
No sh*t really I didn't know that ok great I'll try that.

if I were to post a video of a log while it's doing the weirdness would that help track it down as well with all the values maybe u guys can see what I can't like a sensor reading off?

Can you take a good picture of your engine bay so I can observe all of the sensors and vacuum hoses.

Im visual and want to see what your engine bay looks like to see if there are any visual clues
Yes first thing in the morning I'll take some good pictures of everything thanks man! 💪🏽
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
Can you take a good picture of your engine bay so I can observe all of the sensors and vacuum hoses.

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As you can see 2 of my injector harnesses are still old & I had a harder time getting readings from the noid lights from both so I'll be replacing them just to be sure. I also found my battery ground was completely toast.

I just pressurized the system and hear leaks coming from the throttle body shaft seals could that be my whole running lean problem right there?or is that not significant enough to effect it that heavily?

Oh and BTW I heard bubbling in my oil pan I'm guessing the turbo return oil line is leaking somehow?? Is that bad or normal?
 
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Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
Yeah or you can just unplug the front 02 sensor and see if it runs better after you unplug the connector

Can you take a good picture of your engine bay so I can observe all of the sensors and vacuum hoses.

Im visual and want to see what your engine bay looks like to see if there are any visual clues
Ok so I found this as well the water temp is supposed to be Fahrenheit my & aem sensor was reading 160 degrees according to the emanage the temp is only in the 80's still? Bad ect?
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I asked because if the mechanical timing was off that could have caused both your low vacuum and low compression.

You feel it's 100%, so we'll move on.



I asked about the Solid LA because they require proper adjustment to make sure they don't cause the valves to lag or leak. Just another thing that might be related to your low vacuum and low compression.



That's great, but not what I was asking. There are lots of other things involved that can leak air and cause poor performance.



Again not what I was asking but good to know. It's my understanding that cylinder leak down tests are don't at Bottom Dead Center to avoid the pistons moving and turning the crank. Besides checking if you have leakage into the coolant this test will indicate the general health and give indications if there is leakage how/where it's leaking from. This still relates to vacuum and compression problems.



You may have damaged both sensors by soaking them as well as the electronics connected to them. The problem with holes in front of them is that the exhaust pulses will suck fresh air in, not that exhaust will leak out. This can cause the ECU to not enter closed loop and for your WB to report incorrect values.

A stock ECU can only do so much with fuel trims and I have no idea what if anything the emanage can do.



Trunk mounted batterys have all sorts of failure modes. Both the power cables and the ground cables need to be large enough to carry the current the starters use. When you size those cables you have to take the to and from distance into account. Wires that are too small or have connections that aren't clean and tight can limit the current and cause slow starter problems. But there are other things that can also do so.

If the injectors are pulsing they are likely getting a good enough ground signal from the ECU but may not be 100% up to spec.
Hi I'm sorry to bother you again did some more testing today and I need help I'm not sure how to read my log as well I'll go in order in what I did today.

*inspected ground for battery was very bad I replaced the emergency 100amp battery kill switch- result better crank to the starter but still running lean in different conditions mostly part throttle while rpms are low.

*performed boost leak test- result found throttle body shaft seals are leaking fixed other minor leaks also I heard bubbling in the oil pan I'm guessing from the turbo oil return is that normal?

*while in engine bay w ignition on I was messing with the throttle body I kept hearing a clicking I traced it to the isc but it only happened when I physically wiggled the cts I'm guessing it was a bad connection which led me to my next test.

*ran the emanage software to get a log of the engine coolant temperature sensor readings so I could physically see if they matched my other gauges and came up with a hi 80's as a temp reading when my engine was at around 160 degrees I'll attach the video of the log as well not sure if the car was tuned like that but I'm guessing not.
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
Yeah or you can just unplug the front 02 sensor and see if it runs better after you unplug the connector

Can you take a good picture of your engine bay so I can observe all of the sensors and vacuum hoses.

Im visual and want to see what your engine bay looks like to see if there are any visual clues
Hey man I think I figured it out.as I was scrolling thru my logs I noticed something strange my airflow adjustment correction was in the negatives as it was running lean I kept scrolling to figure out right when the airflow correction stopped my afrs jumped right back to exactly 14.7 on the dot.

So I went to the airflow adjustment tab in the emanage and zeroed everything out and now it's running 10x better.

What could have caused this I'm guessing when I had the car tuned he had to take airflow from the adjustment I'm wondering why now.im guessing either a sensor or maybe mods I've swapped out since my tune? Because it was running perfectly fine with the tune like that for the last 15yrs or so... any thoughts?

Also still getting slightly lean when the car is fully warmed up I'm guessing my tune needs to be adjusted now as well, what do you think?
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
Hi Steve I'm sorry to keep bothering you man but I found a few things today possibly the culprit to what's been going on with the lean condition I'm going to just copy and paste what I wrote to someone else that was trying to help me.

I think I figured it out. As I was scrolling thru my logs I noticed something strange. My airflow adjustment correction was in the negatives as it was running lean. I kept scrolling to figure out right when the airflow correction stopped my afrs jumped right back to exactly 14.7 on the dot.

So I went to the airflow adjustment tab in the emanage and zeroed everything out and now it's running 10x better. AFRs are almost normal now.

What could have caused this? I'm guessing when I had the car tuned he had to take airflthe away from the adjustment I'm wondering why now. I'm guessing either a sensor or maybe mods I've swapped out since my tune? Because it was running perfectly fine with the tune like that for the last 15yrs or so. Any thoughts?

Also, still getting slightly lean when the car is fully warmed up. I'm guessing my tune needs to be adjusted now as well, or possibly the throttle body seals or the flex pipe worn. What do you think?

purchasing the seals now Btw...
 

chrysler kid

20+ Year Contributor
2,600
571
Dec 20, 2002
Mckinney, Texas
After seeing how much of a mess your engine wire harness is, and how messy your vacuum connections are, I cant help you diagnose any further.

Im not familiar with engine tuning so youre on your own there. I try to keep engines and wireharnesses as stock as possible so the car is easy to diagnose and trouble shoot
 

Mike s 95 gst

Probationary Member
28
4
Feb 20, 2016
Pembroke Pines, Florida
After seeing how much of a mess your engine wire harness is, and how messy your vacuum connections are, I cant help you diagnose any further.

Im not familiar with engine tuning so youre on your own there. I try to keep engines and wireharnesses as stock as possible so the car is easy to diagnose and trouble shoot
All of my harnesses broke from being dried out and florida heat I had to rewire most of my wires which obviously weren't the problem I appreciate it though thanks 👍🏼 cars running good now
 
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