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Car chugging at idle, I almost died.

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Araesk

Proven Member
188
1
Jul 10, 2013
Muskego, Wisconsin
Okay so after that first cluster f*** of a post I decided to revise it, make it chronological, and a lot more clear. I apologize to those of you who tried to understand me first message. Anywho here is a recap of what I have done on my car recently over winter and where I started noticing problems.

1) I installed a Begi 2035 Rising Rates FPR and a wally 255 onto my car. (The RRFPR is set to rise as slowly as possible, which should end up being 1:1 IDEALLY.) I took the car out for a spin after installing both of these, and the car ran just fine. (Pic to the vacuum lines for the FPR: http://imgur.com/X5v4OOc)

2) I installed a new wideband innovate wideband o2 sensor. I was curious if the car would drive w/o there being a front o2 sensor, so i started it up without it. The car ran fine as close loop, but once it warmed up and got into open loop it started to run really boggy. It got to the point where I came back outside and I heard the car chugging (the engine was still turning over and firing, but the tachometer read 0 RPM's). I just ignored it and figured the lack of an o2 sensor was the problem. (Note: at this point I had disconnected the ECU and even finished wiring in the wideband, I just had no O2 sensor plugged into it). After I installed the wideband I let the car run again, and it ran just fine. I even let it run for prolonged periods of time so it would definitely be open loop, and I had no problem. I rev'd the engine and watched the A/R gauge, and at about 4k RPM's i was reading high 9's as my AFR.

Now here comes the problem, I took the car out last night for a drive. The car ran beautifully and was shifting like brand new (thanks to a 3 hour job installing skateboard bearings into the base of the shifter cables as bushings). I wasn't letting the car spool at all just to make sure it was running fine. I go ahead and take it out onto the main road to open the throttle up, and the second my car reaches boost, the car immediately starts running boggy and sputtering again like it was after I had no front O2 sensor in. I inspect my car and notice the excess fuel line from my fuel rail to FPR is rubbing against the accessory belt located behind the engine. The fuel line wasn't leaking, it just has a little wear (http://imgur.com/7yS27Xd) in it now from where it was rubbing. I was wondering if that could possibly had somehow yanked the timing off a mark if it got a little to snug (the timing belt is still intact and no obvious signs of damage, will check timing marks Wednesday when i have time).

The other thing I was wondering is that could this all just be from a bad ground? Since my battery's negative to chassis wire is severed on one end so only about 1/5 of the wires are actually still connected (will take a multimeter and check the voltages from battery pos. to neg. and then from battery pos. to chassis and see how they compare.
 
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After reading your mangled excuse for a post I can see why you have problems. First rule of owning a DSM or any car really, is not to half ass repairs or drive around KNOWING there are problems. Break this rule and and you gamble. You lost and your car broke.

Anyway, before even attempting to drive the car again, here is what I would do.

1st: Fix all of the KNOWN problems with your car ie: bad grounds, get a new SHORTER fuel hose, fix the lack of O2 sensor, etc.

2nd: Your car should at least run better now after you fixed the problems with it. Shocker, I know. Anyway, pull the timing belt cover and visually inspect the timing belt and components for problems caused by your lazy hose choice. If they look bad or broken, there's your problem.

3rd: Do a boost leak test, compression test, fuel pressure check, and check the timing. This will tell you any further problems before they occur and let you know the general state of things.

Other thoughts:

What fpr did you install? Is it adjustable, since that is what you need if you install a 255lph pump as it will overrun the stock fpr.

High 9s in neutral is very rich, not lean. If you are in neutral the car cannot build boost so the it should not be that rich. This goes along with the above fpr comment.
 
Alright first of all, you were right about that being mangled so I redid the whole post and it should be a lot more clear now. Second of all, I do not do things half-ass'd on my car. I care about it way too much. Only reason that line was touching the belt is because I didn't know there was a accessory belt that ran behind the engine.

As I updated in the first post, the timing belt still is intact. I will check voltages from battery to chassis with a multimeter on Wednesday, and do the same with checking the timing marks to make sure they line up. If i got time I will move onto a boost leak test. (If this ends up being a boost leak, I seriously will contemplate never posting any problem again until I do multiple tests to make sure there isn't a leak.The car doesn't fire up though like it doesn't when there's a normal boost look. It just kind of sputters to life and starts chugging.)
 
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The edited version is a lot more clear.

You need to put the front O2 sensor back in the car or run a simulator.

I don't know where everyone has got it into their head lately that they don't but you do. The car will do exactly what you are describing sometimes without one.

The boost leak test will also rule that out as a problem as that could also cause that issue.

On your regulator, you should have a gauge on it to check the fuel pressure. That should also be able to tell you if you have a problem there or not.

Doubtful that it's a timing issue.
 
The gauge on the fpr actually doesn't work, so unless it got damaged somehow it should still be accurate. But the o2 sensor is in. Hopefully it's something simple like the boost leak.
Edit: I decided to take a video of what the car starts like. It was even worse this time. http://www.youtube.com/watch?v=HGOg_sc7ON4&feature=youtu.be
 
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Check for boost leaks
Make sure your o2 sensor is working
Check your TPS
You could have an alternator that is going out
Is your bov recirculated? Or are you running Speed Density?
How new are you plugs and wires?
You could check coils, transistor.
How is your Fuel Pressure?

Just some things to check.
 
Buy a new fuel pressure gauge. Install it. Set the fuel pressure at idle with the vacuum line off, to whatever its supposed to be for a 95 2g turbo. Attach the vacuum line and go for a drive. Your fuel pressure could be too high.

Check for boost leaks
Make sure your o2 sensor is working
Check your TPS
You could have an alternator that is going out
Is your bov recirculated? Or are you running Speed Density?
How new are you plugs and wires?
You could check coils, transistor.
How is your Fuel Pressure?

Just some things to check.

This sums it up. :thumb:
 
O2 sensor is brand new.
-Checking for leaks tomorrow. Just got home, way too cold.
-I will check TPS (i'll look around for how to do that)
-Here is an interesting side note. When I was taking off the o2 sensor the first time, my alternator cord was in the way, so in the process of taking it out, I managed to squeeze the plastic locking clip so hard I broke off the locking mechanism. It should still be plugged in though. (I'll triple check tomorrow that is in completely)
-I've got factory MAF and the BOV is recirculated.
-Plugs are like 1.5k on them (NGK BPR6ES), wires are unknown. The pack is not blown (checked).
-Not sure what coils and transistors are. Will look into that.
-Cannot check Fuel Pressure as gauge does not work on it. Probably should order a new one of those.

Here is a video I posted in the edited copy of my prior comment. Just a quick video of a start up, only it's worse than before. Now it just kills itself and doesn't stay running. Video: Not running 95 GST. - YouTube
 
Checking tps (throttle position sensor

Coils - it's where your plug wires plug into.
Transistor will be to the left of it. Don't have a picture at the moment.

Yah get a new gauge so you know your fuel pressure is set.

Check the output of your alternator with a voltmeter.

I can't watch the video right now.

Are you using stock injectors?
If you are, your mbc is turned all the way down correct?
If not, what are you using to tune your bigger injectors? (if you have bigger injectors)
 
Yeah then the coils are fine, I read it could be those so I checked em last night.

The Fuel pressure was perfectly fine before so I do not understand why it wouldn't be working all of a sudden, especially after just some boost.

I'll try hooking up my remote jumper to see if the car will run properly that way, which would greatly narrow things down.

Injectors are stock, and i have my Hallman Pro MBC turned to 7PSI because I didn't have a wideband to monitor the A/F ratios while running the new FPR and wally 255. I didn't want to risk flooding or leaning the car while under boost when I took it out for a spin before messing with the O2 sensor.
 
I'm completely lost. You say fuel pressure is perfect, but you installed a 255 and a new FPR with a broken gauge. How did you set fuel pressure. As mentioned before, sounds to me like pressure is too high and is flooding the engine out.
 
It may be a hassle, but you absolutely need a working FP gauge. You need to know that the pressure is rising at a 1:1 rate, since your post makes me think you have a regulator that can do more, which is unneccesary for your application. I would get a new gauge, liquid filled are the most accurate, and get several feet of hose for it so that you can run it out the engine bay and set it under the windshield wiper. It's ghetto, but its the easiest way I know to watch the fuel pressure while you are driving around. Having the wrong base pressure makes the ecu play with the fuel trims, and can make it difficult for the quick adjustments when the car goes into boost. From everything you have said, I think fuel is your issue
 
The fpr was from a n/t 2g eclipse, and it ran fine after I installed it with boost (It ook it for a test drive and everything was good). I'll go ahead and order a new one here soon and go ahead and check out the pressure. I'll report back again after tonight's diagnostics run and post how they all went.

Could the hood hitting the adjustment nut possibly be increasing the fuel pressure? It sits a little high so I drilled a hole in the bottom layer of sheet metal for it.
 
Get a proper AFPR from a vendor. 2 good and verified reliable ones are Fuel Lab and Aeromotive.

Take this as a lesson in the Buy-Once-Buy-Right department. Then move on and resolve all other hack-job related problems YOU caused to your otherwise fine-running car. (an adjacent lesson in the Do-It-Once-Do-It-Right department)

BTW a lot of things "run fine" that are not fine at all. Running really lean can feel really good and strong, up until you melt a valve.
 
Get a proper AFPR from a vendor. 2 good and verified reliable ones are Fuel Lab and Aeromotive.

Take this as a lesson in the Buy-Once-Buy-Right department. Then move on and resolve all other hack-job related problems YOU caused to your otherwise fine-running car. (an adjacent lesson in the Do-It-Once-Do-It-Right department)

BTW a lot of things "run fine" that are not fine at all. Running really lean can feel really good and strong, up until you melt a valve.

I think before anyone goes telling anyone to go buying knew stuff, they should know everything about how it works and not that it's just a good product. Because I would have just blown an extra $200 dollars on something I didn't need. But then again I should thank you. If it wasn't for your telling me to buy a new one, and my researching into it being necessary (because I'm a teenager working barely part time and am really cheap) I was able to learn how it is that FPR's work. So thank you for indirectly helping me get the answer :applause:

It turns out that it was just the fact that the I had the vent plugged on the FPR so it had no way to release pressure from the system. I was reading up on if I actually would need a new fpr for a 255 and I happened to learn exactly how it is an FPR works, which is: There are 2 connects on the FPR; one is for pressure detection, and the other is for pressure release (just like a intercooler system and it's MBC and BOV). It's crazy I know.) Anywho all i did was unplug both of the nipples to relieve pressure from the FPR and the car started up perfectly. Thanks for all the responses and a special thanks to soccerguy136 for reading my first messy post and sticking with me through it till the end. I will continue to do these diagnostics anyway for preventative maintenance purposes. :rocks::rocks:
 
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