E30 M3.. Throttle position sensor??

[galenthe2nd]

Hi guys,
E30 M3, 1988 and when i start the engine after it sitting up for a few months, it wont take the throttle. It idles poorly and when i plug out the throttle position sensor cable on the side of the throttle bodies it cleans up but still wont take any revs. I have been told this sensor can give trouble, is this correct or any other ideas where to look??

Thanks,
G

[stevesingo]

Does it eventually run clean. or is this permanent?

E30 M3 is very prone to fouling the plugs. Don't touch the throttle when cranking.

Dizzy cap and rotor arm are common faults too.

Steve

[528Sport]

Also if it idles poor when cold change the intake gaskets. I had this issue with mine.
Also what Steve said

Edited by 528Sport on Tuesday 26th January 09:45

[E30M3SE]

What is it like if you start it up after it has been sitting over night?

This may help you out on the TPS.

Edited by E30M3SE on Tuesday 26th January 12:49

[galenthe2nd]

Car was sitting up for 3 months, driven briefly after the first month and ran perfect on a quick blast. Now, when the engine is cold, it starts perfect and will take some throttle for about 5 seconds, then it drops to idle and stalls when i give it the throttle. With the TPS cable plugged out it runs its best, plug it back in and it idles rough again. Going to have the car plugged-in in the next few days. Will check the inlet gaskets and the other areas too.

Cheers
-G

[bananapieface]

Spray WD40 around the inlet gaskets to see if they are leaking, its the heavy alloy plenum that pulls the bodies downwards away from the head.

I think M5 gaskets are the solution but someone will have to confirm, its been a while since I had mine.

[E30M3SE]

Check resistance of the cold start sensor(blue), should be 3k(ish)ohms when stone cold, and 200(ish)ohms when water temp is 90 degC.

How much and how old is the fuel in the tank is another thing to consider, as is pressure, blockage in filter or pump if fuel is very low......??

Edited by E30M3SE on Wednesday 27th January 11:51