Car died, won't start - '89 325i

[FreedS4]

Driving into work today, my car just shut off. No stutter, nothing audible, it just shut off. The RPMs dropped off, all the lights on the instrument cluster came on, and it just died. I pulled to the side of the interstate, tried to fire it back up and nothing. It will crank, but it never catches and starts up. I tried replacing the main relay and fuel pump relay and it does the same, cranks like it is going to start and then never starts up. I replaced the fuel pump with a Walbro unit and still no difference. I had a buddy turn it over, while I listened under the hood and everything sounds like normal, i.e. the fuel injectors seem to be firing, the spark plugs seem to be getting power. There is no other indications of what it could be, no fuel/oil/coolant leaks, no smoking, no noise when it died. Any ideas what else it could be? Thanks in advance.

edit: cliffnotes, check your fuses...

[jlevie]

Is there spark when cranking over the engine at the coil wire? If there is, remove the oil filler cap and see if the cam is turning when cranking the engine. If both of those conditions are satisfied, see if there is spark at each of the plug wires when cranking the engine. If you get this far, check the rail fuel pressure.

[FreedS4]

Is there spark when cranking over the engine at the coil wire? If there is, remove the oil filler cap and see if the cam is turning when cranking the engine. If both of those conditions are satisfied, see if there is spark at each of the plug wires when cranking the engine. If you get this far, check the rail fuel pressure.

I'm beginning to think it's a spark issue and not a fuel issue. Since there was no stumble when it died, it sounds like more of a lack of spark, rather than a lack of fuel. I'm having the car towed back to my house, so I can do more testing once it gets here. Thanks for your help, always.

edit: Would a bad coil cause this?

[jlevie]

It could, as could a bad CPS, bad fusible link, bad ignition switch engine harness fault , or even a bad DME

[FreedS4]

New Bosch ignition coil, no change. Took spark plug 1 out, it's showing a good spark, and there was a subtle difference in the start attempt, meaning there was a difference in the sound it made with spark plug 1 out of the block. It would appear to me that it is indeed a fuel issue. Any other ideas?

edit: The cam does turn when the engine is cranking. And all 6 spark plugs fire when they're out of the block.

[FreedS4]

Ran a few Bentley tests on the DME connector. Here are the results.

Main relay control - Clicks when pin 36 is touched to ground - Good
Voltage supply to control unit - Battery voltage at pin 18 and 37 - Good
Fuel injector control (1,3,5) - Injectors click when 16 touches ground - Good
Fuel injector control (2,4,6) - Injectors click when 17 touches ground - Good
Fuel pump relay control - When 3 touches ground, fuel pump DOES NOT RUN, but I hear a click in the engine compartment - What gives?

Hope this helps narrow down the possibilities...

[FreedS4]

More Bentley tests.

Main grounds - Pins 2,14,19,24 all show continuity - Good
Throttle switch - pin 52 and ground shows continuity - Good
Cylinder id. sensor - pins 8 and 31 tests with less than 1.0 Ohms - Good
Idle air stab. valve - pins 4 and 22 test at 42.7 Ohms - Good
Reference sensor - Pins 47 and 48 test at 557 Ohms - Good

Anyone know how to trick the fuel pump into running? I haven't been able to hear it priming/running since the car died this morning and I'm beginning to think that the fuel pump isn't receiving an electrical signal.

[FreedS4]

Well, after a $60 tow, a $60 ignition coil, a Walbro fuel pump install, and an 8-hour dar trying to track down the cause of the no start/dead car, it turn out to be the No. 11 fuse. Really?!?! A friggin' blown fuse is what caused all of this grief!?!? I guess I can't complain though, I found out the problem without having to pay someone else to tell me what was wrong. Yet another reason why reading the Bentley manual can save you a lot of time and money. It was the first step in the fuel system troubleshooting section that I completely disregarded in the beginning. Although, I will say, something had to cause the fuse to blow, so only time will tell whether or not the problem has been completely resolved.