2000 GTP Fuel Delivery Problem

[addeible]

This is a long story but please stay with me, I REALLY need some expertise.

About three months ago my car started running poorly when in gear but at a stop. It also performed poorly when my foot was off the gas at high speed. It threw a p0440 code about a week later for a purge solenoid valve. After replacing it, it ran a little bit better, but began to throw cylinder misfires. I figured the bad sensor fouled out the plugs which I had been meaning to replace anyway. I put ACDelco wires and Bosch premium plugs in it and it no longer threw codes. It still runs poorly and will even die when I am at high speeds and I apply the break unless I drive two footed and keep my foot on the gas a little bit. I have to take out the plugs and clean this black film off of them every few hundred miles or it will misfire in the second cylinder. If it sits for a couple days, it starts smoking at the rear exhaust manifold (near the second cylinder?) and smells of burning raw fuel. It will also smoke out of the tail pipes and smell of raw fuel. I have been told that it may be a bad carbon canister in the rear of the car, or perhaps a vacuum leak. I keep replacing various sensors only to return them because the performance has not changed. The only sensor that is new is the PSV. Again, it is throwing no codes besides cyliner misfires when the plugs get gummed up.

Any ideas on things to check out would be greatly appreciated. At this point my next guess would be to tear apart the injectors and check for leaks but that would be entirely new to me.

On a slightly less important note I took it to a mechanic who charged me $240 and all he did was put new plugs in it, telling me I had gotten the wrong kind which turned out to be untrue. So I'm done with the notion of taking it to a mechanic as that was both the first and the last time I don't do it myself.

[GTP89]

do all plugs get gummed pics?

[00grandprixgtp]

hey just a though pull the fuel injector rail and cycle the key leave it pluged in and turned on and see if cyl 2 leaks fuel it souldnt leak any...also does it start hard after it sits or anything?

[addeible]

It starts okay after it has sat for a couple days, and it runs slightly better when it is cold. It burns raw fuel and it smokes around the rear manifold and smells of gas.

[GTP89]

try switching the injectors around see if the smoke and misfire follows the injector

[dsmuts]

Bosch platinum plugs are the worst ones you can buy for a gp

[Aeroheadcww]

Dying when you hit the brakes sounds like a vaccuum leak to me, either a hose or intake gasket. If fuel is running out of the engine onto the exhaust manifold then it is probably an intake manifold gasket.

[dsmuts]

lim gasket won't cause gas to run onto the mainfold.

[BillBoost37]

1. Bosch plugs break down quickly in our waste spark ignition system. I would replace them with a nice set of super cheap autolite copper core plugs.
2. If you are dumping excessive fuel then an injector is likely stuck open or over fueling you.

[addeible]

Thanks a lot for the posts! I will replace the bosch plugs but I'm not sure if that will fix the problem. The mechanic put delco plugs in it and it still ran poorly. A friend of mine also suggested I pull the fuel rail so I will try that later today and report back.

[addeible]

I pulled apart the fuel rail and injectors. They were extremely gummed up with grime so I cleaned them with some electronic part cleaner and put them back in in a different order. I also did some research and checked the fuel pressure regulator and I think that may be the problem. I could smell gas out of the vacuum tube and from what I have read that tells me it is bad. I ordered one in at my local auto parts store and it will be in tomorrow. I plan on reassembling the clean injectors, new regulator, new plugs, and fuel rail tomorrow. I hope for the best but at this point expect the worst. Thanks again for the posts.

[addeible]

After putting everything back together it seems to be running a lot better over the past week. It still seems to be burning a little bit of coolant still and I'm not sure what to do about it. What can I check that may cause this problem??

[dsmuts]

Could be the coolant passages in the lim. Should block them off.

[BillBoost37]

I'm sick..I called Dannyo Scotty..

Where's my damn bed?

[dsmuts]

Gtp bill

[Tabitha87]

This is a long story but please stay with me, I REALLY need some expertise.

About three months ago my car started running poorly when in gear but at a stop. It also performed poorly when my foot was off the gas at high speed. It threw a p0440 code about a week later for a purge solenoid valve. After replacing it, it ran a little bit better, but began to throw cylinder misfires. I figured the bad sensor fouled out the plugs which I had been meaning to replace anyway. I put ACDelco wires and Bosch premium plugs in it and it no longer threw codes. It still runs poorly and will even die when I am at high speeds and I apply the break unless I drive two footed and keep my foot on the gas a little bit. I have to take out the plugs and clean this black film off of them every few hundred miles or it will misfire in the second cylinder. If it sits for a couple days, it starts smoking at the rear exhaust manifold (near the second cylinder?) and smells of burning raw fuel. It will also smoke out of the tail pipes and smell of raw fuel. I have been told that it may be a bad carbon canister in the rear of the car, or perhaps a vacuum leak. I keep replacing various sensors only to return them because the performance has not changed. The only sensor that is new is the PSV. Again, it is throwing no codes besides cyliner misfires when the plugs get gummed up.

Any ideas on things to check out would be greatly appreciated. At this point my next guess would be to tear apart the injectors and check for leaks but that would be entirely new to me.

On a slightly less important note I took it to a mechanic who charged me $240 and all he did was put new plugs in it, telling me I had gotten the wrong kind which turned out to be untrue. So I'm done with the notion of taking it to a mechanic as that was both the first and the last time I don't do it myself.

This sounds like my car, only I also have code P0128.

Once the car is on, all I can smell is gas and then when my boyfriend punched the gas (car was in park still) there was a big cloud of bluish-grey smoke. Now we're trying to figure out what the problem is. Did you ever come to a solution for this and did you do a drive cycle to see if the codes came back?

[addeible]

Update...I parked the car for the winter as I am a college student and havent had time to deal with it. Now that it is spring time I am still trying to get it running right. It seems a main cause of my problems was leaking fuel injectors. The fuel would collect above the block and eventually run on to the exhaust manifold. honestly it is a wonder I havent had an engine fire. I have replaced the MAF, FPR, PSV, plugs/wires, as well as a full "service" of the fuel injectors (new upper and lower seals, mesh filter, and retainer clip). I installed them today and it still seems to be missing on a cylinder. The fuel no longer collects on the top of the block which is a good sign. I am going to clean up the spark plugs tomorrow as they may be gummed up from the excess fuel/long sitting time. I will report back if that makes the difference. Fingers crossed.

[rmcardle3]

I am having a similar issue. I changed my oil today and there was fuel in the oil. In addition, the amount of oil should have been no more than 4.5 qt. It was 5.0 qts and reeked of a fuel smell. I just cycled the ignition key to prime the fuel system (I could hear the fuel pump start to run about 3 seconds, then stop). I turned the ignition back off and went immediately to the Schroeder Valve, on the fuel rail, next to the FPR (fuel pressure regulator). I placed a rag under and over the valve and pressed the release pin. No pressure, nothing; it did not even drip wet on the rag. Have you had any luck with yours?