Newbie - E39 523i hot starting problem
Discussion
Not posted on here before and typically start with a problem...
I have a 2000 E39 523i SE manual which I have had for 18 months and 20000 relatively trouble free miles. The car has now done 82000 miles which I believe to be correct and whilst it has been regularly serviced, it has not been serviced by BMW for some time and my trusted local mechanics can't seem to fix this. Apologies in advance for the length of what follows.
From cold, the car starts and runs perfectly. If you restart it within moments of turning it off it generally runs ok too.
However, if the car has been run for 20 minutes or longer, then left for, say 10 minutes to an hour, it restarts as normal but within seconds, the engine cuts out. Upon restart, it generally fires straight up but does the same again. It will then turn over and over but eventually start but then runs "roughly" with reduced power for at least 20 minutes or so. It drives a bit like an old manual choke car that needs a bit more choke pulling out. If you "catch it" the first time you restart it and keep the revs up, it will still cut out (but only once)at the first opportunity - such as approaching a junction.
My mechanics initially replaced a cracked air intake pipe (with genuine BMW part) and when that had no effect, they replaced a coolant sensor. When I took it back again, they advised it needed a replacement camshaft sensor but that BMW would need to do this as the computer would need re-programming. Their diagnostic equipment is not specialist BMW.
My enquiries with BMW suggest that a camshaft sensor is a straight swap, part for part and that the computer would not need re-programming.
I am reluctant to take it to the main dealer as their labour rate is horrendous and would be very grateful if anyone could offer an opinion or direct me towards a good specialist in the Preston area.
Many thanks.
I have a 2000 E39 523i SE manual which I have had for 18 months and 20000 relatively trouble free miles. The car has now done 82000 miles which I believe to be correct and whilst it has been regularly serviced, it has not been serviced by BMW for some time and my trusted local mechanics can't seem to fix this. Apologies in advance for the length of what follows.
From cold, the car starts and runs perfectly. If you restart it within moments of turning it off it generally runs ok too.
However, if the car has been run for 20 minutes or longer, then left for, say 10 minutes to an hour, it restarts as normal but within seconds, the engine cuts out. Upon restart, it generally fires straight up but does the same again. It will then turn over and over but eventually start but then runs "roughly" with reduced power for at least 20 minutes or so. It drives a bit like an old manual choke car that needs a bit more choke pulling out. If you "catch it" the first time you restart it and keep the revs up, it will still cut out (but only once)at the first opportunity - such as approaching a junction.
My mechanics initially replaced a cracked air intake pipe (with genuine BMW part) and when that had no effect, they replaced a coolant sensor. When I took it back again, they advised it needed a replacement camshaft sensor but that BMW would need to do this as the computer would need re-programming. Their diagnostic equipment is not specialist BMW.
My enquiries with BMW suggest that a camshaft sensor is a straight swap, part for part and that the computer would not need re-programming.
I am reluctant to take it to the main dealer as their labour rate is horrendous and would be very grateful if anyone could offer an opinion or direct me towards a good specialist in the Preston area.
Many thanks.
rob.kellock said:
My mechanics initially replaced a cracked air intake pipe (with genuine BMW part) and when that had no effect, they replaced a coolant sensor. When I took it back again, they advised it needed a replacement camshaft sensor but that BMW would need to do this as the computer would need re-programming. Their diagnostic equipment is not specialist BMW.
My enquiries with BMW suggest that a camshaft sensor is a straight swap, part for part and that the computer would not need re-programming.
Time to stop throwing money at your mechanic's guesswork.My enquiries with BMW suggest that a camshaft sensor is a straight swap, part for part and that the computer would not need re-programming.
The sensor is a straight swap as far as I know - plenty of people have changed them on E36 and E46s with the same basic engine as yours.
Have a read of this . .
http://forum.bmwcarmagazine.com/viewtopic.php?t=56...
Particularly pages 11 and 12
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