E30 M10 idle at 1500rpm?

[Jamez 2147483647]

k so i got a 318i m10 that idle's at 1500 once warm and 1000 cold

and i cant figer it out, as its had air con disconnected

also i read that it can go 180km/h but down the motorway i can only get it to 170km/h

and once you get over 5k revs at high speed you can hear like almost sounds like bubbles of air in the fuel pump

i dunno im just guessing what the sound is and where maybe its just air get under a seal sum where

if anyone can help with the idle, it would be most appreciated

and if this is anything

only mods to engine are, K&N filter and new exhaust

oh and it had problems when trying to start on cold days , eg not wanting to idle and not wanting to rev past 3k

[williams 0]

have u tried adjusting the idle down?idle screw sits on the throttle from tappet cover side,and the possible sound could be that u'r prefeed pump isnt working(low pressure)

[CamB 48]

have u tried adjusting the idle down?idle screw sits on the throttle from tappet cover side,and the possible sound could be that u'r prefeed pump isnt working(low pressure)

If he does that it probably won't want to start at all when cold.

FWIW, and based on the limited info provided, I think the auxiliary air valve isn't working and the idle has been turned up to compensate. But realistically this is just a guess.

A huge vacuum leak is also a possibility, which could create detonation ("bubbles of air in the fuel pump" sound?).

I'm really struggling to tie in the "won't rev past 3k when cold".

(edit) OK, so the OP needs a plan:

- check plugs, rotor, cap

- check ignition timing

- check for vacuum leaks

- test auxiliary air valve

Edited October 20, 2008 by CamB

[Jamez 2147483647]

hey thanks for the info ill go over all the tips 2night

[Jamez 2147483647]

turns out

there was a electric cable loose, not of the air filter part but the next part along :lol:lols im bad at explaining

when i connected that back up

that dropped the idle down to 1000

then a lil adjustment on the idol screw saw it go down to a nice 800-900

thanks for the help

[CamB 48]

turns out

there was a electric cable loose, not of the air filter part but the next part along :lol:lols im bad at explaining

That would be the airflow meter, and I'm surprised it ran at all without that connected!

[Jamez 2147483647]

That would be the airflow meter, and I'm surprised it ran at all without that connected!

nah its not the airflow meter unit is the next part along the pipe like just befor it goes of the pipe into the intake manifold, but the cable is wired in the same cable on the afm

zzz i suck at terminology

[Jamez 2147483647]

ahhh after looking in the haynes manual it would seem the "throttle position sensor" was not on and they say without it you get unstable idol ect ect