I need help fast!

[legacy92ej22t]

My car is having a serious issue. It won't stay running. It stalls under boost and seems like it isn't getting enough fuel. It actually will stall when not on boost too. It will stall then it takes repeated attempts to restart the car,. Sometimes it would start and immedialtly die. It really seems like there isn't enough fuel. When I get it to run the car would run good, as long as I stayed off boost, and then it would start running real rough, loose power and then stall. It did this over and over and it just took me over an hour to limp my car home 2 miles. I ttok the cover plate off my fuel pump area because i can't hear it when I turn the key to on. It will make a hiss sound every 3-4 attempts but it definitely doesn't make the traditional whirring sound like every other FP I've heard. Do you guys think it's my FP? I was supposed to be at work over an hour and a half ago and need to either get the car towed to a shop and fixed or fix it myself. I don't have the time or money to randomly change parts out until I find the problem. I think it's the FP and am just looking for someone to say they think it sounds like it too. HELP PLEASE!

[bignose]

i would check to make sure all of your vacuum lines are corrected properly.

[legacy92ej22t]

Thanks but I really don't think it's vacuum. On the rare occasions that I could get it running it ran normal until it st6alled like the fuel pressure was bad.

[vrg3]

Crap.

I'll second the fuel pump possibility, but I can't promise that'll be it.

You have been asking a lot of your fuel system lately, so maybe it just got tired out. The thing is, I don't know if the pump itself really can notice much of a difference since it's supposed to always run at full blast. I suppose the increased backpressure might do it though.

If that place on Lycoming Creek Road has an NA fuel pump they'd sell you cheap you could try swapping it in for the very short term if you're careful to use as little boost as possible.

If that wastegate is actually adjustable and you go down to around 5 psi you probably could actually get away with that for a little while.

Or you could unplug your boost control solenoid and the ECU'll cut fuel if you try to go on boost anyway.

[scottzg]

Have you ever changed the fuel filter?

[boostjunkie]

If you're not hearing the FP charge (did you used to hear it?) then I would suspect the FP to be the culprit.

Although, if you try to charge the fuel pump while the lines are already charged, then you won't hear it.

[legacy92ej22t]

I can still hear it. It is making a hiss sound when it charges and I thought maybe that wasn't the normal sound but Scott came to give me a ride and I listened to his and it sounds the same. So, what else could it be if it isn't the FP? What about the sender unit on the driverside?

When I would get it to start the car would run really rough and I'd have to give it gas. When I'd give it gas it would blow lots of black smoke (unburnt fuel right?) and then once it smoothed out it would be normal and run normal. I'd get maybe a city block and it would start running real rough again and stall. Once it stalled it wouldn't start again until I tried to restart it maybe 4-5 times. Each of these tries it would turn over and fire then die right away like there was no fuel pressure. Then it would finally run rough again, blow smoke, and then run good for about a block then rough and stall! Then I'd have to do it all over again. I'm at a loss. I did notice a couple times that when the car started I heard a gurgling sound from the fuel pump. I thought maybe the pump was dead and I was hearing the engine siphon fuel or something. I don't know. Can anyone think of something besides the FP that could be the culprit?

Oh and the fuel filter is pretty new.

[vrg3]

Hmm.

It does seem like it's a problem with fueling. I do believe black smoke is typically indicative of excess fuel.

I don't think the unit on the driver's side of the fuel pump should prevent the car from running unless you're fairly low on fuel.

It could be an injector that's sticking, or a faulty fuel pressure regulator or FPR vacuum hose, or even an early failure of the fuel filter.

Did you try pulling the fuel pump out and checking the sock filter attached to its inlet? That could be clogged too.

It is possible, though, that the problem isn't with the fuel system. Failure to ignite the mixture can result in transient weird fuel mixtures. Have you pulled your plugs to take a look at them?

[BAC5.2]

Spark plugs seem like it could be the culprit. Oil fouled the plugs and erratic spark would throw unburnt fuel into the exhaust. It's not unlikely that at such high boost, you are getting a bit of blowby that's causing spark plugs (that might already be somewhat pooched) to become covered in oil.

Pull a plug and take a look.

If the plugs look OK, then why not run some of that "fuel injector cleaner" through the tank and see if that helps? Couldn't hurt, eh?

[legacy92ej22t]

Ok, I did a D-check and the first one threw a code 45 but it was my fault. I forgot to hook the vacuum line that goes to it back up. I did it again and got the all clear which I shouldn't get anyways because my O2 sensor shouldn't be registering. Plus it gave me the all clear really quick (like almost immediatly) even when I was having the problem.

Anyway's while checking just now the car will drive normal for a bit, then run real eratic and get worse. The rpm's and vacuum will both go up and down like a bad IAC or something at idle then eventually stall when I try to move or after moving and putting in the clutch it will stall. The car will idle normal sometimes too and as soon as I touch the accelerator pedal it will stall. It's very eratic. I need to fix this and I don't know what to do.

[scottzg]

Bad gas?

[vrg3]

I would check the fuel pump sock and the plugs.

[evolutionmovement]

I second that, and suggest maybe stuck injectors. Could it be a TPS or the like? You said it dies when you hit the gas so I wonder if there's a sensor going bad. I most suspect fuel, though, since you're really overworking that system, while the other systems are less concerned. Hm. What about the MAP sensor?

Steve

[legacy92ej22t]

I do have a code 45 in my R-check but it doesn't throw the code in D-check.

Could this have something to do with the way we wired the O2 sensor signal wire Vikash?

I checked the plugs and they are fouled, they're black and I can smell gas on them. They are fouled up as a direct result of the problem though. When I give the car gas to keep it from stalling it blows black smoke (unburnt fuel) so that's why the plugs are fouled, right? Hmmm, maybe this is an ignition problem? What could cause it besides the plug wires (almost new) the plugs (good shape except they're fouled because of the problem) and the coil pack. I'm going to try swapping coil packs to see if that's the problem but I really doubt it.

It's weird because when I first start the car cold it will run normal and I can drive it a little ways normal too, then it acts up and gets worse and worse. Could it be heat related or that when something warms up, like the O2 sensor, it starts? Maybe the O2 sensor is getting a signal now Vikash and making everything screwy? Just thinking out loud here.

[Tleg93]

If there's even a possiblility that it could be the FCD maybe you should cut it out of the system carefully. We could always re-install it at a later date. Seriously though, why not revert the car back to normal boost and remove the FCD until you can figure out what's up, just a suggestion.

[legacy92ej22t]

Well, I don't really think it's the FCD. I may lower boost if I can get the car running but, well, I need to get it running first.

[Tleg93]

I see, but isn't it at least possible that you may need to lower the boost to get it running in the first place? I may be ignorant but isn't the increased boost causing more fuel to be used? And if you are burning more fuel, couldn't that have caused the spark plugs to foul out, especially if a lot more fuel isn't getting burnt?

[vrg3]

Did you clear the codes successfully? Cuz R-check displays codes that happened in the past even if they're not still active.

It could have to do with the oxygen sensor... If the problem appears right when the car should be going into closed loop, that's suspicious.

Since your sensor's not working anyway, you might just want to cut the wire that we added. You can just snip it under the dash after it comes through the grommet.

If it seems heat related it could also be something like the coolant temperature sensor. Or it could be any electrical connection under the hood.

Or it could just be that the car's automatically idling high when cold and masking the problem.

Scott's suggestion isn't a bad one... even though I don't believe the FCD could be involved it's always good to go back to stock. You'd just have to snip out each of the leads going to the FCD and then splice together the one wire that we cut.

Didja check the fuel pump sock?

It makes perfect sense to reduce the boost, but I don't think Matt's going on boost in these tests. Are you, Matt? Cuz you shouldn't.

And did you double- and triple- check for vacuum leaks?

[legacy92ej22t]

Yes but this problem is occuring off boost. I never even get to boost and I have the problem. The car will run good sometimes for a short while too so to me that means that it isn't just a plug issue. It's something changing as I drive. Either loss of fuel, loss of spark, a sensor not working or the ECU freaking out and doing something weird. Problem is that I don't know which and I don't know how to trouble shoot it. More acurately I have idea's of how to trouble shoot it but I don't have the time. I'm watching my kids then I work until later tonight. Same thing tomorrow. First day I have off is Sunday and then if I figure out what's wrong and it's a dealer part I won't be able to get it. Any way you look at it I'm pretty much fucked. It's looking like I'm going to have to have it towed and pay some jack ass to fix it for me which I can't afford.

[legacy92ej22t]

That last post was responding to Scott.

[Tleg93]

Oh, I didn't think about that. He's most likely not running boost. I was just trying to eliminate the mods that were done recently. It seems a little too coincidental that the car is running poorly just after it has been worked on.

[legacy92ej22t]

Did you clear the codes successfully? Cuz R-check displays codes that happened in the past even if they're not still active.

I can't clear my codes, remember? I have no idea how old the codes but I think almost all of them are old.

It could have to do with the oxygen sensor... If the problem appears right when the car should be going into closed loop, that's suspicious.

Ya, it's right when the car is starting to be warmed up that it happens. Then it stays bad until the car sits a while.

Since your sensor's not working anyway, you might just want to cut the wire that we added. You can just snip it under the dash after it comes through the grommet.

I was thinking about doing that. It's worth a shot since it's not working anay ways.

If it seems heat related it could also be something like the coolant temperature sensor. Or it could be any electrical connection under the hood.

I know and that has me REAL worried.

Scott's suggestion isn't a bad one... even though I don't believe the FCD could be involved it's always good to go back to stock. You'd just have to snip out each of the leads going to the FCD and then splice together the one wire that we cut.

I really don't want to cut it out when we just got it working right...

Didja check the fuel pump sock?

No, I haven't had the time. Seems like that would present itself slowly though doesn't it? Seems weird that it was so sudden if it were a dirty sock.

It makes perfect sense to reduce the boost, but I don't think Matt's going on boost in these tests. Are you, Matt? Cuz you shouldn't.

Nope, no boost at all. The couple of times that I started getting any boost at all was when it first happened and it would immediately die.

And did you double- and triple- check for vacuum leaks?

No, but when I get it to run normal, on those very brief occasions, the my vacuum readings are good.

Could it all be the IAC valve?

[vrg3]

Oh yeah, I forgot you wouldn't be able to clear codes. I don't think you need to worry about the code 45 since it's not coming up with D-check. Don't bother with the FCD if you don't feel like it; I'm almost positive it's not causing this problem.

Yeah, go ahead and clip the oxygen sensor wire that we added. Let's rule that out. It'll only take you a couple seconds.

The sock could plausibly have just sucked up a leaf or a piece of rust or something that somehow made it into the tank. Then as the pump works it swishes around and doesn't cause trouble until it gets stock on the sock again.

I agree with your implicit suggestion that it's unlikely to be a vacuum leak because when it runs normally vacuum is good, but it still might be something to look for. It could plausibly be an intermittent vacuum leak.

I don't think just the IAC valve could do this; the fuel mixtures would still be mostly right even if the engine stalled and stuff.

I'm sorry this is happening, Matt.

[evolutionmovement]

Well, what changes with temperature? At start the computer advances timing and enriches fuel, but when warm it drops both, so ... I'm not sure what that means. Usually the temp seems to fail and cause starting issues, but maybe there's more than one failure mode? The ECU checks the o2 even when cold? What other sensor is crossreferenced with the o2 for fuel/timing? MAF? I'd think the MAP sensor would be more of an on-boost problem ... The IAC shouldn't be doing this as it's just idle, the cam and crank sensors wouldn't do this. What's left to eliminate? TPS, o2, MAF, MAP, temp, or a combo. Couldn't be plugs as a colder plug would foul easier, but you wouldn't want a hotter plug with the extra boost and I think it would start harder with too cold a plug. I'm still wondering if there are some sticking injectors. Maybe they were beat up by the increased duty and age and now they can't be counted on to act reliably. Just thinking aloud.

Steve

[vrg3]

Yeah, as it warms up timing advance falls back a little and the fuel mixture un-enriches a little. And the IAC valve duty cycle drops a little.

I was thinking that temperature might be messing with a marginal electrical connection, though.

The sticking injectors thing is certainly a possibility... There's a good chance the injectors spent some time at 100% duty cycle, stuck wide open, while Matt was boosting big on the TD05. That could overheat them. But I thought injectors usually stuck closed when they failed, not open.

Hmm. It could be a failing injector o-ring or something. Hmm. If an o-ring is leaky and letting fuel dribble into the manifold when the car's sitting, then it would be very hard to start. When it did eventually start, you'd get a tremendously rich condition. But when that excess fuel gets blown out you'd get an okay mixture. And then when fuel pressure goes up again when you start driving, you could push the leak open a little wider and cause the problem to start all over. Hmm.

This is all armchair diagnosis, though.