BMW 540i Erratic Idling

[guyp]

Hi All,

I have a 2002 BMW 540i with the motorsport kit and mag wheels (and M bading). I started the car early yesterday morning and it idled like it had hot cams! The engine warning emmission light keeps flickering. The car seemed to idle erratically for quite a while now but yesterday morning it really got worse and then cut out.

Any help will greatly be appreciated!

Cheers

guyp

 

[Raybimmer]

Cats still in the exhaust ?

 

[guyp]

Cats still in the exhaust ?

I take it it you mean catalytic convertor? Yes.

 

[Jandre]

Did it struggle to idle and then dies down, smelling of petrol ?

sounds similar to what my e34 did the other day. Turned out to be a breather pipe on the back of the engine.

 

[clutchplate]

eish, can be quite a few things... but it sounds like an airleak.. could also be MAF or injectors or a plug.

take the engine plastic cover off and listen carefully for a sucking/vacuum sound get someone to rev the engine very low rpms till 1500 and listen for it...
then wet your hand with a little bit of water.. moist, not wet... and then feel where the draft is going

hope u come right bro. let us know

 

[Truvalu]

Good luck man...

I have found my 528i sometimes catch me with a very unpleasant smell when I stopped after driving short distances in town. It smells like old oil burning!

Ihave had her for four tanks already and have not had to add any oil and there is no visible signs of any oil leaks anywhere.

Could it be cats?

 

[guyp]

Did it struggle to idle and then dies down, smelling of petrol ?

sounds similar to what my e34 did the other day. Turned out to be a breather pipe on the back of the engine.

It struggled to idle and then dies down but no petrol smell.

:thinking:

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eish, can be quite a few things... but it sounds like an airleak.. could also be MAF or injectors or a plug.

take the engine plastic cover off and listen carefully for a sucking/vacuum sound get someone to rev the engine very low rpms till 1500 and listen for it...
then wet your hand with a little bit of water.. moist, not wet... and then feel where the draft is going

hope u come right bro. let us know

Thanks! Will try that. To add further to the problem especially when the BM is still cold and I stop say at a robot, the idling falls below 500 revs and it almost feels like the brakes are not functioning. It feels like the car then moves a few feet forward. :thinking:

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More issues!

The petrol range indicator seems to be inaccurate. Car showed 79km range left last night. Driving this morning it went down to 46km range then luckily as I pulled into the petrol station she ran out of petrol again.

The problem the other day was fuel starvation but the car especially cold still idles erratically.