I wanted to take my e36 325i out for a day, the car started and drove fine as usual, got about 3 miles into my trip when it suddenly died and wouldn’t start again, just kept cranking. After checking over the car and trying to find an issue I could find nothing. Then a few hours later it started again but not for long, a couple more hours later she started again and managed to get it closer to home before it died again, waited again and got onto my driveway.
The gauge cluster shows the car is at normal temperature and wasn’t overheating, battery has good voltage, when the car dies it just goes down in revs till the engine is off, can anyone give ideas as to what could cause this?
Fuel pump. Had the same issue on my Lexus.
I would check the fuel pressure, it sounds like a dying fuel pump
Fuel pump or crank sensor/cam sensor
A weak fuel pump can be to blame. If it’s not maintaining at least 30 psi to the engine, the gas can vapor lock in the lines from the heat from the engine. Once it cools off, the vapor condenses, collapsing the bubble and allowing fuel flow again, for however brief a time before the engine heats up again.
Nobody has said it yet but I think this could be cam / crank position sensors. Had the same symptoms and it was that. Different car though.
I had an E36 325i with the M52 and found it was my crank angle sensor. From experience the cheap crank and cam angle sensors are unreliable and to prevent future issues its worth buying oem or a high quality replacment.
Had this issue on my miata, the original sensor sometimes freaked out it got hot. Car died and wouldn’t start. Once it cooled down, worked again for a while until it got hot again. Not sure if this is a common issue here but might be the explanation.
Pull a wire and see if you have spark after it stops running. That tells you fuel or ignition.
Jump the fuel relay
Fuel pump is going bad, gets hot and shots off.