OK. I'll try and be brief as to the problem and remedies so far...

I had an intermitent missfire which got progressivily more frequent. It would clear after a few miles but last week it didnt clear back onto 4 cylinders for over 150 miles.

I have changed the plugs, leads, coil pack and even the airflow meter which needed doing anyway. The problem still persisted so i moved my attention to a fueling issue rather than electrical.

I pulled plugs off all injectors one by one and found the faulty cylinder (number 1)... as it made no differecnce to idle when i removed it! I then presumed it could be a knackered injector.

Before going ahead and replacing the injector i did a compression test to ensure all was how it should be and it came out good. I then put some Slick50 (redex stuff) into my tank and this had an immediate effect but just really reverted it back to the occasional missfire (missfiring for approx 3-4 miles before clearing) so there was still a problem.

I was then convinced the injector was badly blocked or unservicable.

I've now this evening replaced the injector on the culprit cylinder. Took it for a run and its definately improved but if i dump my foot on the throttle and pump the fuel through it still wants to missfire....

Also - the injector i took out had some kind of black sooty type material on it.. should this have been there? Is that the 'redex' cleaning the crap out??

Can anyone give any other suggestion as to why this f####n thing is still playing me up. I dont know what direction to take next.

Pleeeeeease help...

Peace.

 

try posting your problem in this section

Sounds like you might have a faulty coilpack. What year & model is it?

 

Have changed the colipack bruv. I was so convinced it was the colipack i even purchased a third one to be 100% sure i hadnt purchased a faulty 2nd hand one...

I've posted it where you suggested cheers.

I hope someone can help cos i'm scratching my head !

 

Oh... its a 97 WRX. Any suggestions... PLEEEEEEASE!!!

 

head gasket maybe mate . burnt valve or summat

 

Cheers.

Wouldnt it be runinng on 3 all the time tho if headgasket had gone?? Besides water levels look good and no 'dangerous' looking smoke from the pipe.

If a valve was burnt.... again would this not cause it to run on 3 constantly? I'm no expert but as it keeps clearing and missfiring intermitently surely its not an internal problem like a ring or valve ?????????

Please tell me i'm right or wrong... i really dont know.

 

May be a red herring BUT my classic had an intermitant starting problem/miss fires and after changing various parts the thing that cured it was the Cam Shaft sensor.......... prior to that I had replaced the Crank sensor, water temp sensor & Ignition amplifier...............

The coil packs were replaced by me a Year before as a precaution as the car had hit 90,000 miles and the belt/tensioners were done too.

 

is there any chance it could be fuel pressure problem ? or the pump being weak as it doesn prime on start up then after a while builds up pressure to clear ? i really wouldnt do 150 miles with a miss mate .

 

if your definitely sure its that cylinder that's giving you problems and you have changed the injector then i would say it might be wiring issue's , so firstly check you have a 12v feed to onside of the injector then check the the switched earth from the injector to the ecu

 

Did you do a leak down test ?

 

Thanks for the input gents....

Whats this. Is it easy to do?? Ta

Funny you mention intermitant starting because it has failed to start a few times and i thought it was the starter motor so just cleaned up all the terminals. When i turn the key, it will sometimes be a good 2-3 secs before it starts! Were is the cambelt sensor located. Worth a try thanks.

Was thinking possibly fuel pressure but not sure how to go about what to replace... (had no choice with the 150miles... was ****tin it every time i had to drive it!)

Me & electrics dont get on.. thats for the direction though.