Engine ignition problem with 02GT

[FadeToOne]

Hey guys,

I started having a problem with my car last week...maybe someone around here can diagnose before I bother going to a dealer to check it out.

Helpful specs:
2002 GT
Manual Transmission
41.5k miles
~5k miles since last oil change, but oil seems fairly clean to not have caused a problem

Mods:
Cold air intake
X-Pipe with MIL eliminators
Catbacks

Problem timeline:
Last Monday 8/8: While leaving for work, starting up the car created the usual engine noises, and after about a second died with a few thuds. Attempting to start the car again was successful, and the car ran fine. This happened every time I started the car that day; 1 failed start followed by success.
Tuesday - problem seemed to disappear
Wednesday - Service engine soon light comes on - the only error on the odometer display is dtc5284 (oil pressure switch failure) which I've read is fairly common
Friday - Engine ignition problem returns, but now it's more intermittant
Saturday - We disconnect the battery and decide to change out the spark plugs on a hunch. After that, the first start seemed okay, but the problem occurred again later in the day.
Sunday - Service engine soon light comes on again (as it went off when the battery was disconnected)

So that's my story. As I said, the car runs just fine after it starts successfully. My dad was pretty big into repairing cars back in his day, but he is stumped. One of my theories is that the fuel filter could be dirty. Hopefully this problem is not too severe.

Thanks for any suggestions you can provide.

 

[Dark Knight GT]

When was the last time the fuel filter was changed and when was the last time you cleaned the IAC ?

My advice is this. First, change the fuel filter. Next, Remove and clean the IAC. After this, some Seafoam through the intake might be a good idea, as well as adding some to both the crank case and fuel system. This will help clean out the motor in all ways. Another thing to check for is loose ignition coils. This can be the cause of ignition failure. Try all of these and report back if you still have problems.

 

[Black1987Stang]

any update on this?

 

[dustang50]

I had the same problem a few years ago. The car was under warranty, so I took it in. They said the fuel pump was going bad, and that in the process a bunch of crap was released down the fuel line. They took out the fuel filter & tapped it a few times on a desk, and a bunch of black crap came out of it - small flakes & such.

 

[Mike97gt]

could be the fuel pump. or a bad iac. or a million other things too

does this failed start happen when the car has been sitting for awile. like a cold start in the morning. if it only happens durring inital startup after the engine cooled down, then your problem maybe the fuel bleeding out of the line and back into the tank. when you cycle the key to the on position the fuel pump runs to build fuel pressre. if the pump is allowing to much fuel to drain back then you will have a failed startup.

to test for this. next time you go to start up after the car sat for awile, cycle the key a few times from off to run (not the start pos. just untill the dash lights up) let it sit in run for a few seconds then back to of. do this 3-4 times, then try to start the engine. If it starts fine the first try then the problem is the fuel pump.

 

[Black1987Stang]

could be the fuel pump. or a bad iac. or a million other things too

does this failed start happen when the car has been sitting for awile. like a cold start in the morning. if it only happens durring inital startup after the engine cooled down, then your problem maybe the fuel bleeding out of the line and back into the tank. when you cycle the key to the on position the fuel pump runs to build fuel pressre. if the pump is allowing to much fuel to drain back then you will have a failed startup.

to test for this. next time you go to start up after the car sat for awile, cycle the key a few times from off to run (not the start pos. just untill the dash lights up) let it sit in run for a few seconds then back to of. do this 3-4 times, then try to start the engine. If it starts fine the first try then the problem is the fuel pump.

Yea...just wondering cuz mines been doing it alot, mostly in the morning after it sits overnight, it would stall if i didnt give it gas, and after it sits for a couple hours it will do it but not as bad. Its a new 255lph pump and it still did it with my old pump but one of my injectors are leaking(hotwired the pump and heard 1 injector is making a psh sound and my fp drops within a minute) so im sure thats why. I have tried priming the pump once or twice but still did it, prob left an air pocket somewhere and it stalled since there wasnt 100% fuel in the rails yet. Ill start it tomorrow and look what happens to my fuel pressure when it starts. and when i get time ill throw in a spare 19lb injector i have laying around. Hope this is the problem

 

[sgarlic]

If you would've taken it somewhere to have the check engine light diagnosed, you would've known right there what to look for.

You can't just run the HEC diagnostics when you get a check engine light, that's the CLUSTER diagnostics, and stores trouble codes for the cluster.

You have to download MIL codes with an OBD2 reader of some sort.