Running very lean! (log)

[eclipsyco]

Hey guys need your help here!
So long story short… the car been sitting for like 7 months during those months I changed multiple things like new turbo and exhaust manifold, 3" ss turbo-back exhaust, clutch master and ss line, aluminum radiator etc (profile is up to date)
After that the car was running fine a had a few exhaust leaks so my wideband showed a 15.x AFR and I assumed was due to the exhaust leaks (02 housing). I took the car to be painted so it was sitting there for like 2 weeks during those to weeks a chanted the TB elbow as well as new gaskets for the TB. And then it happens I fire it up to warm her a bit after to weeks sitting and my AFR was all over the place like 19.x to 20.x I thought I didn't properly tight the bolt on the TB and had a huge vacuum leak, so I turn her off double checked everything and fire it up... again same thing but this time CEL came on but since i didn't have my mac with me I just call it a day. Next day (this being yesterday). See LOG file please

Got code 0100 which is MAF and apparently my o2 is not cycling either but no CEL for that the other 1500 code ignore it is been there since i got the car is due to not oem alternator
So two sensor died at the same time?WTF Is maybe some thing else that is wrong and make the sensors not working? I already removed the the whole exhaust manifold to seal the leaks and unbolt the o2 and removed the maf (note a use a GM MAF in a blow throw set-up) I'm going to order these any time soon but I want some input if maybe could be something else wrong.
P.S. I know I have to retune my TPS is way off etc.

 

[Chicken Patty]

From looking at the log, you are not getting a MAF reading nor a Front o2 sensor reading. Check the connections, it'll be too much coincidence that both failed at once.

 

[eclipsyco]

Thank you for the input I already check the connection and are clean and tight! I already got the o2 sensor and tomorrow the MAF so I'm going to try again and post a log. I think I have my stock MAF laying around so if the new MAF doesn't work maybe is the ECM cable... I hope not!

 

[Chicken Patty]

Thank you for the input I already check the connection and are clean and tight! I already got the o2 sensor and tomorrow the MAF so I'm going to try again and post a log. I think I have my stock MAF laying around so if the new MAF doesn't work maybe is the ECM cable... I hope not!

Okay, keep us posted. Post another log and I'll take a look at it.

 

[eclipsyco]

Okay, keep us posted. Post another log and I'll take a look at it.

Ok I'm back so here's the deal I swapped the o2 sensor with a brand new one. I tried 2 GM MAF and the stock MAF as well… Same issue so i'm stumped.
I pulled my ECU which still looks in near perfect condition.

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So now the only thing I can think of before replacing my ECU, is a wiring problem a bad ground or a no signal to the ECU but if that the case why would it affect only two sensors and not the rest? Do the o2 sensor and MAF shares the same ground? if so where it is? Tomorrow I'm trying again I'll take my multimeter this time and check every single wire! Do you have any inputs maybe something I'm overlooking?
Is been very humid here cause it rains a lot the car doesn't get wet tho could the weather cause this? corrosion?

 

[eclipsyco]

Hey guys! Sorry to keep bringing this up but I truly need your help I'm all by myself and I work on the car myself. The only dsm buddies I have are like 300km (180+ miles) away and they do what they can to help me. This shit is driving me nuts al the wiring is good the ECU ground tested good as well. The GM MAF is a good known working one an the o2 is brand new. Is there ANYTHING that could cause just those 2 sensors not to work!?

 

[92AWDHX40]

could be some bad wiring at the connections.

 

[eclipsyco]

could be some bad wiring at the connections.

I test continuity from pin to pin (sensor to ECU) every single one of them al tested ok!

 

[92AWDHX40]

Sounds messy, maybe a bad wideband sensor.

 

[eclipsyco]

Man if you take a look at the log on my first post you will clearly see that I'm not getting signal to those 2 sensors the ECU tho can see them or else they would appear in grey as a non captured data. A body suggested me that It might be a huge boost/vacuum leak in the manifold area is this a possibility? And would it throw a CEL for that?

 

[snowborder714]

A big boost leak would not throw a CEL, nor would it cause your MAF or front o2 to not read.

Have you verified all grounds (chassis and sensor) with a multimeter, as well as pinned out both sensor's plugs?

 

[eclipsyco]

A big boost leak would not throw a CEL, nor would it cause your MAF or front o2 to not read.

Have you verified all grounds (chassis and sensor) with a multimeter, as well as pinned out both sensor's plugs?

To my understanding the o2 as well as the MAF they share a common ground as well as many other sensors to pin 92 which is the grounded inside the ECU.
So what I did was I checked continuity between PIN number 5 (ground) on the MAF engine harness to the black wire (ground) on the engine harness for the O2 I got continuity then I probe them to PIN number 92 and got continuity as well! So my grounds are ok right?

 

[eclipsyco]

Hey guys I notice something today when put the key into on or ignition my ISC moves and make a funny noise for like a second I never heard my ISC doing that before. And since those sensors share ground and 12+ with other sensors could this be my problem I didn't test the ISC I just didn't have enough time to take it out and test coils nor a turn on the car to see if my problem
was fixed since I don't have the IC piping hooked. So to resume is normal for the ISC make a noise when on or ignition?

* ISC/IAC

 

[snowborder714]

Yes it's normal.
[ame=http://www.youtube.com/watch?v=l7R3gf7SiAo&list=UUUUuGdILVsVOdtygQVj6haQ&index=11&feature=plcp]DSM ISC - YouTube[/ame]

 

[eclipsyco]

Oh I see, well that was kinda disappointing! Thanks

 

[Chicken Patty]

I still say two sensors going out at once is very strange. I am leaning more towards wiring issue or ECU. Can't seem to comprehend two sensors failing at once, and to further prove that, you have swapped them. As suggested above, maybe grounding issue.

 

[eclipsyco]

Could a bad MFI/MPI relay cause this problem? (I dont think so really)
So lets forget about the o2 for a sec I did the following with the maf and tested OK
"Backprobe terminal 4 of the connector with the positive probe of the voltmeter and connect the negative to the ground. Turn the key to on but do not start the engine if the voltemeter does not read around 12v. If so check the circuit back to the MFI relay and fusible link.

Backprobe terminal 3, it should read 4.8-5.2v with the key on. If not check the circuit to the ECU.

Backprobe terminal 5 with an ohmmeter and measure the resistance. It should be less than 2 ohms. If not, check the circuit from terminal 5 back to ground.

If none of the above work, the MAS or ECU is dead. Replace it."

Still no signal to the ECU en CEL on! how is that even possible??
I'm really starting to suspect my ECU is bad!

 

[snowborder714]

Have you been testing with the ECMtuning GM MAF cable attached and using that MAF plug for your readings, or have you been testing directly to the factory MAF plug?

If from the ECMtuning cable, I'd suspect a bad cable. Only way to test this is send it back or replace with a known good cable.

If not, then you might have a bad ECU or something else very weird going on.

 

[eclipsyco]

Have you been testing with the ECMtuning GM MAF cable attached and using that MAF plug for your readings, or have you been testing directly to the factory MAF plug?

If from the ECMtuning cable, I'd suspect a bad cable. Only way to test this is send it back or replace with a known good cable.

If not, then you might have a bad ECU or something else very weird going on.

Actually a tried both last test was with the MAF plug and I tried using my old stock MAF which when I pull it off over a year ago it was working.
I'm going to send my ECU to a friend of mine who has a 95 GSX so it's a plug and play so he can test it!

 

[eclipsyco]

Ok guys just to let you know I solve the problem!
So to everyone know it was a combination of issues
1. Huge exhaust manifold leak (manifold to turbo) which was making my 02 go lean first 02 was bad too!
2. I was not getting the +5v and the +12v was very weak this was due to moisture on the cables to much resistance! (Had to replace the whole cables)
3. The GM ECMtuning cable for the MAF was bad too! Never really actually test it but after three GM MAFs I assumed the cable was the problem since after replacing the cables in the stock plug the stock MAF was working!

So after all this MAF thing I got fed up and just switched to SD! Runs and drives fine! Still learning how to tune with SD!
I still believe that the problem was due to a short-circuit on the battery and also for sitting for a while in a very humid place.

 

[Chicken Patty]

Ok guys just to let you know I solve the problem!
So to everyone know it was a combination of issues
1. Huge exhaust manifold leak (manifold to turbo) which was making my 02 go lean first 02 was bad too!
2. I was not getting the +5v and the +12v was very weak this was due to moisture on the cables to much resistance! (Had to replace the whole cables)
3. The GM ECMtuning cable for the MAF was bad too! Never really actually test it but after three GM MAFs I assumed the cable was the problem since after replacing the cables in the stock plug the stock MAF was working!

So after all this MAF thing I got fed up and just switched to SD! Runs and drives fine! Still learning how to tune with SD!
I still believe that the problem was due to a short-circuit on the battery and also for sitting for a while in a very humid place.

Glad you got it fixed. Seemed like a bit of a nightmare and shitty luck, but you didn't give up.

If you need some pointers on tuning SD let me know. I'm know my way around tuning pretty well. Best of luck.

 

[eclipsyco]

Glad you got it fixed. Seemed like a bit of a nightmare and shitty luck, but you didn't give up.

If you need some pointers on tuning SD let me know. I'm know my way around tuning pretty well. Best of luck.

Yes, it was a pain. I still need to properly seal al leaks and adjust my idle to be able to tune I mess with it a little bit cause I was tuning very rich and now drives "fine" I'm staying away for WOT tho! I'll PM if I need your help thank you!

 

[Chicken Patty]

Yes, it was a pain. I still need to properly seal al leaks and adjust my idle to be able to tune I mess with it a little bit cause I was tuning very rich and now drives "fine" I'm staying away for WOT tho! I'll PM if I need your help thank you!

You got it bud.

 

[96accordsir]

good thing you fixed it. I was thinking definite exhaust leak to go that lean after only changing parts.