E39 M5 starting issue
Discussion
Im getting quite bored of this now.
Pretty much every time I try and start the car, it either just cranks over, coughs and then continues to crank over or it'll start and then stall. The second attempt 90% of the time sees it start.
It had a replacement fuel pump fitted in June and this started happening a few weeks into my ownership.
I know it is due plugs, it doesnt report any errors when codes are read either.
Car is a '99 V Pre-face lift. Any suggestions / help much appreciated.
Thanks
Pretty much every time I try and start the car, it either just cranks over, coughs and then continues to crank over or it'll start and then stall. The second attempt 90% of the time sees it start.
It had a replacement fuel pump fitted in June and this started happening a few weeks into my ownership.
I know it is due plugs, it doesnt report any errors when codes are read either.
Car is a '99 V Pre-face lift. Any suggestions / help much appreciated.
Thanks
you found out why the old fuel pump failed.
I only ask this because from the little youve said it sounds like fuel starvation.
If you replaced the old pump, and found the old pump to be working 'on the bench' then your problems lie in the same area
so did you prove the old pump was faulty?
I only ask this because from the little youve said it sounds like fuel starvation.
If you replaced the old pump, and found the old pump to be working 'on the bench' then your problems lie in the same area
so did you prove the old pump was faulty?
julian64 said:
you found out why the old fuel pump failed.
I only ask this because from the little youve said it sounds like fuel starvation.
If you replaced the old pump, and found the old pump to be working 'on the bench' then your problems lie in the same area
so did you prove the old pump was faulty?
Pump was replaced before I bought the car, so I do not know why it failed.I only ask this because from the little youve said it sounds like fuel starvation.
If you replaced the old pump, and found the old pump to be working 'on the bench' then your problems lie in the same area
so did you prove the old pump was faulty?
Sometimes it will start first time.
I've seen this before and the most likely fix is to replace the fuel tank Activated Charcoal Filter (P/N 16 13 6 752 623) and/or expansion tank (P/N 16 13 1 184 480). The filter or the valve in the expansion tank gets blocked which causes a problem with the pressure/vacuum in the pipe that feeds back to the fuel tank breather valve (P/N 13 90 1 407 474) under the plenum.
Other possibilities are the fuel pump relay, the pre/post cat O2 sensors and check for exhaust cracks around the O2 sensors, ignition switch, EWS, crank position sensor and a load of other unlikely stuff.
Other possibilities are the fuel pump relay, the pre/post cat O2 sensors and check for exhaust cracks around the O2 sensors, ignition switch, EWS, crank position sensor and a load of other unlikely stuff.
RichardM5 said:
I've seen this before and the most likely fix is to replace the fuel tank Activated Charcoal Filter (P/N 16 13 6 752 623) and/or expansion tank (P/N 16 13 1 184 480). The filter or the valve in the expansion tank gets blocked which causes a problem with the pressure/vacuum in the pipe that feeds back to the fuel tank breather valve (P/N 13 90 1 407 474) under the plenum.
Other possibilities are the fuel pump relay, the pre/post cat O2 sensors and check for exhaust cracks around the O2 sensors, ignition switch, EWS, crank position sensor and a load of other unlikely stuff.
Hmmm, sounds like I'm in for spending a small fortune!Other possibilities are the fuel pump relay, the pre/post cat O2 sensors and check for exhaust cracks around the O2 sensors, ignition switch, EWS, crank position sensor and a load of other unlikely stuff.
The fuel pump relay (I believe its the right one in the boot anyway) does have some scorch marks on the pins.
Where is the Charcoal filter located?
Thanks Richard.
I actually disconnected the fuel tank breather valve on my car for some time with no effect on starting the car. Considering its only used to scavenge fuel vapour I don't see how that could be the problem. It might concievably cause uneven running due to letting air into the inlet bypassing the mass flow sensors but thats about it.
IMHO I think the changed fuel pump is your clue. Someone highlighted this as a fuel problem before and changed the obvious thing without working out why. You might be closing in with the relay. Ideally you want the problem to reappear and then change or bypass the relay for a short period to check you've solved the problem.
IMHO I think the changed fuel pump is your clue. Someone highlighted this as a fuel problem before and changed the obvious thing without working out why. You might be closing in with the relay. Ideally you want the problem to reappear and then change or bypass the relay for a short period to check you've solved the problem.
TheAngryDog said:
Hmmm, sounds like I'm in for spending a small fortune!
The fuel pump relay (I believe its the right one in the boot anyway) does have some scorch marks on the pins.
Where is the Charcoal filter located?
Thanks Richard.
The Charcoal filter and breather tank are up in the drivers side rear wheel arch. The expansion tank is quite expensive, I think the Charcoal filter is no so bad.The fuel pump relay (I believe its the right one in the boot anyway) does have some scorch marks on the pins.
Where is the Charcoal filter located?
Thanks Richard.
I've seen people swapping out all sorts of stuff, fuel pump, relays, cam sensors, crank sensors, O2 sensors, MAFs, spark plugs, injectors, new keys ... and almost all with this specific problem have been fixed by replacing the filter and/or breather tank.
The problem seems to be more prevalent AFTER fitting a new fuel pump and can be temperature sensitive too, very cold and it's not so bad, hot and it's not so bad, between 5 and 20 C happens 9 times out of 10.
TheAngryDog said:
Im getting quite bored of this now.
Pretty much every time I try and start the car, it either just cranks over, coughs and then continues to crank over or it'll start and then stall. The second attempt 90% of the time sees it start.
It had a replacement fuel pump fitted in June and this started happening a few weeks into my ownership.
I know it is due plugs, it doesnt report any errors when codes are read either.
Car is a '99 V Pre-face lift. Any suggestions / help much appreciated.
Thanks
Did you get the fuel pump from Euro Car Parts by any chance?Pretty much every time I try and start the car, it either just cranks over, coughs and then continues to crank over or it'll start and then stall. The second attempt 90% of the time sees it start.
It had a replacement fuel pump fitted in June and this started happening a few weeks into my ownership.
I know it is due plugs, it doesnt report any errors when codes are read either.
Car is a '99 V Pre-face lift. Any suggestions / help much appreciated.
Thanks
It could also be a crankshaft position sensor too....
Thanks again for the replies guys.
The previous owner fitted the pump, and it did indeed come from Euro Car Parts.
The reason it was replaced was because the car cut out and wouldnt start again, just spin over.
The pump resolved the issue and it fired up once fuel pressure had been built.
The previous owner fitted the pump, and it did indeed come from Euro Car Parts.
The reason it was replaced was because the car cut out and wouldnt start again, just spin over.
The pump resolved the issue and it fired up once fuel pressure had been built.
RichardM5 said:
I've seen this before and the most likely fix is to replace the fuel tank Activated Charcoal Filter (P/N 16 13 6 752 623) and/or expansion tank (P/N 16 13 1 184 480). The filter or the valve in the expansion tank gets blocked which causes a problem with the pressure/vacuum in the pipe that feeds back to the fuel tank breather valve (P/N 13 90 1 407 474) under the plenum.
Other possibilities are the fuel pump relay, the pre/post cat O2 sensors and check for exhaust cracks around the O2 sensors, ignition switch, EWS, crank position sensor and a load of other unlikely stuff.
This 100 %. On my first M5 the fuel pump let go and was replaced by a genuine BMW in tank pump. It lasted 6 months then let go. I got another free from BMW which never missed a beat and was still going strong when I got rid of the car.Other possibilities are the fuel pump relay, the pre/post cat O2 sensors and check for exhaust cracks around the O2 sensors, ignition switch, EWS, crank position sensor and a load of other unlikely stuff.
You need to stop listening to advice from the internet first.
Its not going to be the inlet of outlet camshaft sensors if, as you say, the diagnostic was normal. The inlet and outlet position sensors are logged faults not temporary, so they will appear on the diagnostic if they have a problem.
Its unlikely to be a tank breather if I can run my very happily without it, just by blocking it off.
How about a bit more diagnostic. Prove its a problem with the fuel by putting a pressure meter on the fuel rail, or stick a meter to teh terminals of your fuel pump and see if the fuel pump relay is working properly.
Otherwise you are going to buy a whole bunch of suggested stuff with no guarantee of it doing anything other than draining your wallet.
Its not going to be the inlet of outlet camshaft sensors if, as you say, the diagnostic was normal. The inlet and outlet position sensors are logged faults not temporary, so they will appear on the diagnostic if they have a problem.
Its unlikely to be a tank breather if I can run my very happily without it, just by blocking it off.
How about a bit more diagnostic. Prove its a problem with the fuel by putting a pressure meter on the fuel rail, or stick a meter to teh terminals of your fuel pump and see if the fuel pump relay is working properly.
Otherwise you are going to buy a whole bunch of suggested stuff with no guarantee of it doing anything other than draining your wallet.
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