1G misfire no check engine light

[TW 92 talon tsi]

i have got a problem with my 92 tsi when my car sit for a while i go to start it it starts fine, but when i wait a bit it starts to misfire not all the time though, some time it happens when i drive down the road. The strange thing is that the engine light dosnt come on. so i tried resetting the computer and it stopped, but not for long so every time it happens i just reset the computer and it is fine. i just want to know before i go buy a new computer. has anyone had this proble and it was the computer?? the reason i think it is the computer is because it dosnt respond to the issue. is that right??? thanks

 

[NB4G63T]

I wouldn't buy and ecu, if anything being a 92 its probley and eprom ecu, good to have. Have you did a tune up lately plugs and wires?
I'd try that first

 

[NB4G63T]

NGK wires and plugs FTW.



Edit: a misfire isn't going t trigger a fault code all the time, so I don't think resetting ecu is really doing anything, maybe but doubt it.

 

[GRAVEDIGGER]

Definitely do a tuneup on it before you go throwing a computer at it. Replace the fuel filter, spark plugs, and wires and see what happens.

 

[TW 92 talon tsi]

ya i have done a tune up i also have rebuilt the head changed cam position sensor, fuel pump, water pump, fuel pump relay, but the thing is it drives perfectly fine after resetting the ecu. it is driving me crazy ### when i took it to my mechanic it dosnt do it so he cant hook it up to see if what fault codes are showing up if any are.

also when it misfires the car shuts off when i try to let it idle or it idle eratcally and so i try starting it again and it dose the same thing so then i reset the ecu and it starts and runs fine then it dosnt do it somtimes for up to a week

thanks for all the replies

 

[GRAVEDIGGER]

It would be nice to see what is going on with the computer when you are having your problems. Without solid proof of what is going on it's just a shot in the dark.

 

[NB4G63T]

Maybe a sticking injector IDK, got a spare set you could try.

 

[TW 92 talon tsi]

thanks alot for your help i will check the injectors out i am not sure when they were replaced not since i have owned the car so they probly should be changed

 

[LunarEclips]

Not a sticky injector. It would constantly stay open or closed....not work when it wants to? misfiring this bad should throw a CEL. Alot of non check light problems could be:

Boost Leak
faulty connections to majors sensors i.e o2 sensor, temp sensor, cam sensor, (especially east coast drivers)


Its most likely electrically related since if you reset the ecu, the problem goes away for quite a while. I would say start scanning through your sensors, looking for freyed/spliced wires, etc.

EDIT: I was also thinking maybe about a bad coolant Temp sensor. During high heat, it sends signal to the ecu. The ecu in return advances or retards timing accordingly to compensate for the heat. Did you car smoke at all when it idled rough and died? did the mechanic pull the plugs when it was idling like crap to see if it was running rich or lean?? Were all four cylinders firing during this rough idle period? Alot of these questions can pinpoint solutions.....

 

[Urban Tellez]

Did you ever figure out the problem?I'm from Denver. I just bought a 1991 gsx and it starts idling rough after a while. No check engine light and dark smoke comes out when its rough idle