need help

[robo]

Can anyone pls help.. got H plate 320i and have a mindbendingly anoying cutting out prob. I've changed/elliminated the following so far:

Air flow meter, blue/brown coolent temp sensors, idle valve, ECU and fuel pump. Can't see anything obvious like frayed wires anywhere. It starts up ok from cold, runs till just about working temp, then just gives up the ghost. Will start back up ok (but not always straight away, sometimes not till after 5 - 10 mins before will start again). It always starts fine from cold. When it does cut out, it could be on a straight or a corner, but not one necessarily or the other. It will run again ok, but will cut out once again. I'm just about at the end of my tether, and am considering killing it, which would be a shame, because when it does run, its a belter of a little motor as you guys know they are.

Thanks for any help or advice in advance you guys may be able to give me.
Kev
P.S. All three relays within the fuel relays box on passenger side of engine bay have been checked - all ok.

[Martinaston]

Pull the spark plugs and let us know what colour they are.

[Brianmoooore]

:
P.S. All three relays within the fuel relays box on passenger side of engine bay have been checked - all ok.

Checked as in changed?

[Brianmoooore]

Don't see crank position sensor in the list.

[robo]

Nice one guys, spark plugs checked ok - nice & brown/grey, not glazed/shiny white core or anything, or oily. Fuel relays were checked by RAC with a lap top meter, haven't explored the crank postion sensor yet though, can you expand on this please mate, i.e. location & what to look for & what is best to do, i.e. replace the sensor or something. Cheers again lads.

Kev

[Brianmoooore]

I'd trust my seven year old to test the relays rather than RAC/AA, having watched them in action once or twice.
The CPS is on a bracket next to the toothed crank pulley, front right of the engine. You can confirm a dud one is dead with a resistance meter, but yours is intermittant, so replacement is the only certain check, preferably swapping it onto a good engine.
They often become temperature sensitive intermittant, and the symptoms are no fuel and no spark, although sometimes they will give a weak miss timed spark, just to confuse things a bit.
Would still change the DME and fuel pump relays with scrapyard ones first though.

[robo]

Ha Ha, cheers Brian (poor old AA/RAC blokes, they do get a bad press with many people, I hear what your saying). What do you mean by the DME?

[Templ8e30]

Digital Motor Electronics.

It's the white relay in the box on the inlet side of the engine bay, it controls the supply to the ECU.

Along with the fuel pump relay it can give intermittent cutting out/non starting problems even if they appear to be ok.

Cheers,

Iain T

[robo]

Nice one, cheers Ian mate. Does everyone know what time it is, here we are sorting out our (my) problems with our cars. Its great, I can't quite drag myself off to kip though.

Kev