1986 735i

[alanworth]

My 735 will start up, run fine for 5 to 10 minutes and then quit on me. Won't start right away. If I wait five to fifteen minutes it will start again. Sometimes it will sputter while other times it silently dies and I roll to a stop. I thought it was a fuel line or fuel filter problem. Someone at the parts store says it might be my coil on its way south. "Car warms up, coil bonks out and cools down, and then it will run for a while." I'm not much of a mechanic but money situation demands that I take a crash course and search out help. I just ordered a repair manual and would appreciate any input on this problem.

[Dirty_Tool]

The 1st thing to do is to determine when it dies what is dropping out. Is it the ignition, or is it the fuel supply. try to recruit a friend to help you on a weekend so that when it dies he can crank over the car for you while you check using a spark tester or an extra spark plug for spark. Also if you have a fuel pressure guage available then it would be wise to just connect it inline with the fuel pump and leave it connected while you drive that way when it dies you can quickly see if it is a fuel pressure issue. Once you narrow it down to either a fuel or spark issue then you can pinpoint it from there. While I dont disagree with the parts guy that it could be a coil issue I would also be really suspecting that fuel pump. Anyway, do the checks I recommended and then posts the results. If you need additional help from there myself or someone else can probably offer more suggestions.
Good Luck,
DT

[alanworth]

Originally posted by Dirty_Tool@Apr 7 2005, 09:47 PM
The 1st thing to do is to determine when it dies what is dropping out. Is it the ignition, or is it the fuel supply. try to recruit a friend to help you on a weekend so that when it dies he can crank over the car for you while you check using a spark tester or an extra spark plug for spark. Also if you have a fuel pressure guage available then it would be wise to just connect it inline with the fuel pump and leave it connected while you drive that way when it dies you can quickly see if it is a fuel pressure issue. Once you narrow it down to either a fuel or spark issue then you can pinpoint it from there. While I dont disagree with the parts guy that it could be a coil issue I would also be really suspecting that fuel pump. Anyway, do the checks I recommended and then posts the results. If you need additional help from there myself or someone else can probably offer more suggestions.
Good Luck,
DT

[snapback]328098[/snapback]

Thank you for the input. I'll start working on it today.

AW