Intermitent problem

[otto]

Ive had this prob with my car for a while now that i and the mechanic have tried to fix to no evail and its driving me nuts, so i thaught i might hand it over to the experts (you guys) in hope that one of you might point me in the right direction.

Ok every now and then and these days its more often now than then, my idle will hunt IE, drop down to below 500rpm then back up to over 1000 rpm and while its doing this its blowing puffs of black smoke out the exaust sometimes it will sort itself out and other times it will stall.

If i then try and drive/acellerate while its playing up power will feel like its surging , i feel the surges more when im on the freeway and accelerating in a higher gear sometimes the surges get so bad the engine will shut down for a split second and when it does it will also puff smoke (it will also ppuff smoke when its surging but not as much. if i throw it into neutral when it surges it will hunt at idle.

any ideas? would love to hear them cause its really making me hate my car!

[Bobjones]

Possible causes may be dirty AAC valve, AFM may have crap on it...

Do a quick search on Stalling and it will come up. This problem is often caused by running overly oiled pod filters or general dirt and dust.

[otto]

Sorry should have mensioned i have cleaned the aac valve swapped afms, cas, replaced plugs. it just got its 100k sevice aswell!

i dont think its got anything to do with the aac as the problem is all over the rev range not just at idle. usually when im on the freway accelerating up a hill.

[predator]

sounds like your fuel pump or something is a bit dodgy? or the wiring to it or something?