1999 astra 2.0 sri running problems

findlay

was just wondering if anyone can help as my astra is not running as it should!! the car somtimes goes down onto two cylinders and engine management light comes on if you switch off ignition and start the engine it gets past it and EM light goes out, sometimes it can go a day or so without doin this and other days it does it all the time, sometimes once it starts doing it you have to stop start it loads over the space of ten miles to get it to run on all four cylinders and get EM light to go out. the longer this problem goes on the worse it gets HELP??
ive had tech2 on it and it said there was a mass airflow meter fault so ive changed that and ive tried new egr valve new temp sensor new spark plugs but not leads i could try new leads but im now thinkin it might be coil pack!! id like to see if anyone can help and has perhaps came across this problem as i dont want to spend anymore money on things that aint fixin it!!
ALL HELP WOULD BE GREATLY RECIEVED

mitch1965 · Posted: Mon May 07, 2012 7:46 pm Post subject:

I'd pull the plug on the ecu & dose it with wd40 to start with, do the same to the coil pack & check your earth straps. smile

Ash · Posted: Mon May 07, 2012 7:58 pm Post subject:

Was the replacement AFM new?

findlay · Posted: Mon May 07, 2012 11:31 pm Post subject:

No they weren't new I've tried three different ones!! I've wd40'd coil pack but not the ecu plug I'll give it a try
Thanks I'll let you know how I get on

Ash · Posted: Mon May 07, 2012 11:55 pm Post subject:

My mate changed 4 on his corsa before he found a good second hand one. Best off finding someone with the same engine willing to swap a few parts to diagnose the problem.

timewellnick · Posted: Tue May 08, 2012 8:17 am Post subject:

Hi, have you tried changing the lambda sensor, or crank sensor? They give similar faults to this sometimes. Having said that it could well be a coil pack, but dont they usually just stop working all together?

findlay · Posted: Tue May 08, 2012 3:30 pm Post subject:

ive wd40'd coil pack and no change and ive looked everywhere and cant find the earth straps if memory serves me correct from other vehicles there should be one from the body to the gearbox and i cant remember where the other normally is!! havnt tried lambda sensor or crank sensor!! ive never had lambda issues with a car in the past so not sure of the symptoms ive had crank issues before on cars and it seems that anytime ive had crank sensor issues in the past the car either wont start sometimes or is very reluctant to start my car fires into life first turn of the key!! if were out driving the car and was going along at steady speed and the revs were over 2500 car is fine and if i let the revs drop too much the EML comes on and it starts running off cylinder, hope this other info helps and can find me a cause of the problems. and i forgot to say ive also changed the idle control valve.
thanks

mitch1965 · Posted: Tue May 08, 2012 8:32 pm Post subject:

Its possible its the cam sensor breaking down when hot then? maybe just check its plugged in ok. Yeah there's a belt for earth from chassis to g/box, also to usual places such as slam panel from battery & then to alternator and starter motor, sometimes one from alternator to head. Confused

I woud also try another maf, there's times when these are duds to start with.

findlay · Posted: Tue May 08, 2012 9:57 pm Post subject:

Thanks ill try lookin again for these straps i almost definatly cant find one comin from gearbox but ive never seen a car that doesnt have one comin from gearbox so must be there!! ive had cam sensor unpluged and pluged back in again no change, i didnt think it was a cam sensor problem as ive changed a few in the past and the symtoms they all had were when the car was climbing up the revs once it would get to 3500 it would be like it was hitting the rev limiter and wont go higher my car revs up as normal!! ill just keep trying and you can think of anything else let me know or if anyone else has any clue's let me know as this problem is gettin on my nerves and i cant really use the car now!!