E30 spluttering from warm start

[cbeattie]

Hi there, recent joiner to the zone.
Have been trawling the forums for similar symptoms and have found a few but none that match mine exactly.
My E30's problem is that the engine is spluttering and stalling from a warm start.
Absolutely fine from cold, and usually trouble free from a 'very warm' start - i.e. turn off and back on immediately.
No errorcodes showing on diagnostic machine my mechanic has.
My mechanic reckons crankshaft position sensor or ignition related fault and has decided the best thing is to replace this and see if the problem goes away. Not sure what else to do as previous mechanic had no clue and don't want to keep replacing parts indefinitely.
Any advice appreciated.
/Chris.

[Brianmoooore]

Blue (ECU) temperature sender is the first thing to try.

[cbeattie]

Just suggested this to the mechanic who thinks not related to temp sender.

Maybe i didn't describe the fault well enough initially.

He's thinking the problem is ignition-related (it's like the ignition just cuts out - which results in spluttering if moving, and engine stall if not).

[Gwynleym10]

Car doesn't overheat at all does it?

Also check vacuum hoses for cracks, do this VERY carfully especially the the big bellow between the Air flow meter and Throttle.

While this may not help its worth cleaning out the AFM and throttle with Carb cleaner.

Is you mechanic a BMW specialist? I would be inclinde to belive Brian about the Blue temp sensor. They are only £16.

Welcome to the Zone by the way!

[Adammcf]

Blue (ECU) temperature sender is the first thing to try.

Was gonna say the same.

[Demlotcrew]

Blue (ECU) temperature sender is the first thing to try.

Was gonna say the same.

Yup me too

Andrew

[Chris-W]

Blue sender is the natural first thing to check, although I had the same symptom on an M40 once which turned out to be a cracked dizzy cap. Only showed it's face once the car was up to temp.

[georob]

Had the same sorta prob for a while but it was nothing to do with blue sensor

Will check what it was

[Brianmoooore]

Blue sender is the natural first thing to check, although I had the same symptom on an M40 once which turned out to be a cracked dizzy cap. Only showed it's face once the car was up to temp.

Distributor cap was to be my next suggestion if the temp sensor change didn't work.
Crank position sensor is a posibility, but they usualy fail completely after a week or two of acting up.

[cbeattie]

Thanks for the responses.

Car doesn't overheat - does that mean not the temp sensor, or is it still worth checking / replacing?

Mechanic is not a BMW specialist, but seems to know what he's doing. Well, it seems to me that he knows what he's doing.

I'll pass on your advice and will check the distributor and hoses.

What's AFM? Something to do with air filter?

[Brianmoooore]

Blue temp sensor is the one the tells the EUC how hot the engine is, so that it knows if to add extra fuel for a cold engine.
AFM = air flow meter. Sits on top of the air filter housung.

[m-dtech]

what part of edinburgh are you ?

im in falkirk if thats any help ?

[cbeattie]

actually, i work in larbert m-dtech, so am pretty close.

were you offering to have a look at the car?

would be very helpful if you were!