E30 Zone

quick question lads. 987 325i cab. when i start the car the car idles perfectly at about 6000rpm. sometimes the rev meter jumps up and down for a minute then is fine again. no problem at all when the car is been driven. also, after the car is warm, everytime i brake to stop the car for eg. at traffic lights. when the car stops the rev meter goes very low and then jumps back up again to normal? any ideas?

also noticed when checking throttle body. the there is a pipe that leads from the inlet manifold to the throttle body cover. this pipe seems to have cracked. could this be it?

I'd be looking for a vacuum leak first of all, then havijg a look at the AFM.

Hope the 6000rpm idle speed is a typo!

i mean 600 rpm lol. do u think it just needs a good clean withe sum old carb spray? and do i just check the pipes for cracks and holes.

Give the ICV a clean with some carb / brake cleaner and inspect the inlet side for cracks/leaks.

Do you mean the hose in between the coolant pipes, on the side of the throttle housing?

If so, that hose goes from the throttle housing heater cover, under the inlet manifold and connects to the top of the valve cover. It is part of the crankcase breather system and if there is a crack in it, it will effect engine idling.

cheers chris. youre a star. if not sorted ill be bak for you haha

Easy test for inlet leaks.

run car to fully warmed up, open bonnet and remove the oil filler cap with engine running @ idle

no change= intake leak and the cars been bodged about to get around the issues

runs like crap/hunting, almost defo no intake leak

Works like a charm

also true of any engine with a closed loop engine breather setup.

will do that now and let you know in a bit. cheers guys

ant, i left the engine till the temp guage was in the middle. opened up the oil cap and the engine started chocking and hunting, it didnt cut off though. i take it thats a good sign? whats the next step boss?

I,d go for the ICV and give that a damn good spraying of carb cleaner and see how that goes then on the AFM matey

ill do dat on da weekend. cheerz boys

Just out of interest does the car idle fine when rolling in neutral or clutch in but a second after you stop start to dip get down to about 550rpm stutters fuel eco gauge flicks flicks to the left and then it revs up to 800-900rpm then starts over again? If it is then i pitty you because I've been searching for the fault on mine for over a year.

im not sure if it does that, all i know is when the car starts to get warm, the rev meter just jumps between 300rpm and 900rpm for about 20 seconds to a minute and then totally stops. when i drive the car it doesnt affect the drive at all, but sometimes just before the car stops, the rev meter jumps. also when i slow down to very slow speeds to go over a hump it does it.