Having issues with car. Help wanted
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Joined: Feb 2003
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From: Kansas City, Mo
Having issues with car. Help wanted Just got the turbo setup running good on my 2002 Camaro last week. Drove the car a lot all last week with no issues. Drove it last saturday night for a bit before the rain came and Sunday morning went to go wash it and the car would not idle above 400rpms and anytime I would give it gas it would just die. I am running E85, 2 A1000 fuel pumps (one on a switch), no MAF, 3 bar map sensor and stock pcm. I have been trying to track the issue down all week but have came up with nothing. I did add 50% more fuel in the tune and the car would start up and run, rev up with good throttle response but it would idle at 2,200 rpms. I thought it could have been a vacuum leak so I pulled the intake manifole off and inspected for leaks. Found nothing. Put my normal tune back in the car and same issue. Will start up like normal and after about 5-10 seconds of run time it will die. I also cleaned my fuel filters before and after pumps, I have good fuel pressure with key on. I also swapped out the map sensor thinking that could be it, found nothing. I have picked just about everyones brain on this I know of. Any help would be great.
-Justin-
-Justin-
Throwing parts at a problem until it goes away is usually a bad idea.
It sounds probable you have a vacuum leak. What happens when you do have a vacuum leak with a speed density tune is you idle in a different cell. One that isn't dialed in for a no-load, idle situation. It would be great if you had a log of the car idling fine and compared it to now. You could look at injector pulse width, what cell you're in and how many kPa you're idling at. Any higher kPa value could be a vacuum leak. You could have knocked your IAC valve connection loose or something like that. It would be wise to cap off the inlets to your F/I system and try pressurizing everything through the brake booster line and looking for leaks.
While it's idling, you can look at your LTFT (if they're on, but I keep them off), your STFT values, your IAC position, your TPS voltage/position etc.
Could be that the throttle blade got shut beyond the ability of the IAC to control your idle.
It sounds probable you have a vacuum leak. What happens when you do have a vacuum leak with a speed density tune is you idle in a different cell. One that isn't dialed in for a no-load, idle situation. It would be great if you had a log of the car idling fine and compared it to now. You could look at injector pulse width, what cell you're in and how many kPa you're idling at. Any higher kPa value could be a vacuum leak. You could have knocked your IAC valve connection loose or something like that. It would be wise to cap off the inlets to your F/I system and try pressurizing everything through the brake booster line and looking for leaks.
While it's idling, you can look at your LTFT (if they're on, but I keep them off), your STFT values, your IAC position, your TPS voltage/position etc.
Could be that the throttle blade got shut beyond the ability of the IAC to control your idle.
Wish we had more free time to look at it, we'll be out of town this weekend though. We got all those other issues sorted out for ya, I'm sure we could figure this out also.
Thread Starter
Joined: Feb 2003
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From: Kansas City, Mo
I thought vacuum leak to but I have no idea where it would be coming from. I have took every single line off, intake manifold off and inspected it all. Nothing looks to be wrong with that stuff. I would think it would have to be a pretty big vacuum leak to need 50% more fuel. Could I have a bad fuel pump if its still got good priming pressure? The car doesnt stay running long enough to look at fuel pressure after its running. I am running the FIC 160's
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Thread Starter
Joined: Feb 2003
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From: Kansas City, Mo
The car will not run long enough or steady enough to see running fuel pressure. I do not tune the car or have any type of scanning tools. My tuner came over to my house the other night to see what it was doing. That is when he added 50% more fuel to get the car to run. It had a lot of codes in the system. Wish I could tell you which ones they were.
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Verdad Gallardo After performing the pressurized vacuum leak test, if you come up empty, I would recommend you put it back in the scenario where it runs with double the fuel and the high idle and work on it from there. Should be much easier to troubleshoot when you can log and pull codes.
160s can be picky, and do some odd things when moving VE values and hardly seeing a reflection in AFR. How much did the AFR move with 50% added to the VE Table? What is your IDC at WOT currently? You may want to back fuel pressure off quite a bit and retune if you suspect its an injector controlling issue.
Does your throttle body still have side to side play? Could be that, could be a tps issue, could be a vacuum leak. May have nicked an injector oring?
Does your throttle body still have side to side play? Could be that, could be a tps issue, could be a vacuum leak. May have nicked an injector oring?
Thread Starter
Joined: Feb 2003
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From: Kansas City, Mo
Ryan, the tb seems to be fine. I fixed the issue it was having. Justin is going to come over tomorrow and help me with it so I can see whats going on in the computer. I wrote down everything posted in here so I can go through it all when I start working on it again.
I would eliminate the fuel system as the problem before doing anything else. You need to get some idea of running fuel pressure. Static pressure let's you know the pump is turning on but doesn't indicate if there's enough volume of flow.
The car will not run long enough or steady enough to see running fuel pressure. I do not tune the car or have any type of scanning tools. My tuner came over to my house the other night to see what it was doing. That is when he added 50% more fuel to get the car to run. It had a lot of codes in the system. Wish I could tell you which ones they were.
* I re-read your first post. You introduced water to it. Check all your sensors/connectors... take them off and blow them out. I see this often working on electrical related stuff. If you close the circuit on a sensor (short its signal with water) you send the PCM into haywire mode making it recieve false signals.
Last edited by pwrtrip75; Apr 20, 2012 at 12:35 PM.
Alot of good suggestions in here, have you verified the turbo is still turning freely? I've had some funky issues in the rain. Double check to make sure you battery terminals are tight. Some cars I've tuned in speed density had a weak battery and some reason would not fail the maf like they should so they wouldn't start up at all until the battery had a good charge.
Thread Starter
Joined: Feb 2003
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From: Kansas City, Mo