2002 BMW 530i Sport E39 - starting problems

[ams]

Hi - sorry this is my 1st post
I have a 2002 BMW 530i E39 - it starts from cold fine but occasionaly after a short run - it wont start up. The engine turns over and I can hear the fuel pump running but it does not fire up. If I leave it for a while and go back to it - it starts. I have chnaged and air filter. - but its made no difference. Because its so intermittent - it is hard to diagnose - for example - it wasnt starting so I took one coil off, plugged a spark plug in and checked it sparked - it did - but the car started as well!

Any ideas

Thanks in advance.

[rashid]

Strange, have the same car with around 350,000Km on it, but have not experienced such problem. I had a bad experience with the chaging motor & replced it two times.

With my limited experience, I advise you to do the following:

Check the charging motor.
Check the battery connections & claen the connectors.
Remove all spark plugs, claen them & put them back in again.

update us on the progress ...

[ams]

Not a power problem - starter turns over fast when it doesnt start. - Have changed the battery anyway, but no difference to the fault. Also put a new set of plugs and filters in. Have also changed the crankshaft sensor. Will be changing the 2 camshaft sensors next. Its only done 70,000 miles and never been abused.

[rashid]

Have you taken it to an experience mechanic?

[ams]

Yes but because it is an intermittent fault - it is almost impossible to diagnose.

[witeshark]

Maybe it's an unreliable connection in the ignition system.