Misfire when vehicle idles " can anyone help?"

[manassa]

Can someone please help me?
i've got a 1998 vauxhall astra CD 1.6 16v. i recently had my piston rings changed at my local garage and thats when the problem started. took it back but they couldn't find the problem. the timing was spot one, inlet manifold gasket was ok , engine warning light is not on. it only misfires on idle as soon as you accelerate it stops, and when driving no problem loads of power and a smooth drive. but i have noticed i consume slightly more petrol.don't know what else to do.. HELP

[lala_1981]

hi mate could it be the idle control valve!!

[manassa]

WE took the idle control valve off and cleaned it but no change.

[odyssey2200]

My guess would be that you might have an air leak into the manifold after the meter.

Check for a manifold gasket leak
Check all vacuum and rubber pipes for splits/missing etc.

[manassa]

I'll have a look and i'll get back to you after the new year. can't be ask at the moment thats a head fk.. cheers

[Silent1]

Sounds like unmetered air is getting in to me

[The Riddler]

MAF sensor?

If not check the convoluted air pipe between throttle housing and MAF sensor, they tend to split under vacuum load if driven too hard.

[callyman]

Have you sorted this yet? I ask as on a 2.0 16v (redtop) an incorrect plug gap can cause it.

[manassa]

That was the first thing i done, but there was no change. i also notice when driving at low revs it does it slightly. its like when there is no stress on the engine it happenes