Hey Everyone
I have an 88 740, with the 2.3 non-turbo. I parked it at my friends house on a slight incline (passenger wheels on a curb) and went to a football game. When I got back it wouldn't start up. The starter its self is fine so I replaced the ignition coil to see if that was the issue but when testing the path to the coil, it turns out that I'm not getting a spark to the coil at all. The fuses are fine but there's one more thing. The fuel pump doesn't start pumping after moving the igntion switch to "on" without actually trying to start it. So the fuel pump isn't working for some reason also. Anyone else have an issue like this? I'm trying to figure it out before I buy a **** load of parts I don't need. To me it seems like an electrical issue. Thanks in advance guys.

 

Spray some starting fluid in the intake. If it fires up momentarily you have a fuel problem, otherwise electrical. Got battery and fuel, right?

Hold off on changing parts *****-nilly.

 

if no spark OR gas, Id be looking at the hall sensor and its wiring first.

 

Tried the starter spray approach when I initially discovered the issue and it didnt start at all so it's gotta be electrical, I'm going to check the hall sensor and wiring today and I'll update afterwards. thanks guys

 

SO i had a little bit of time with the car last night, not enough to do anything major but i checked the wires that go to the ignition coil. When their disconnected it measures 12 volts across, perfectly normal. But when connected to the ignition coil (both the old and new one) it measures 0. The positive wire sparks when disconnected and is tapped against metal. so it could possibly be the negative wire? ANyone know where that wire goes from the coil?

 

the wires on the side of the coil, pin 15 (blue wires) goes to ignition switched power, the other side, pin 1 (red-white wires) goes to the power module, which in turn pulses it to ground to make spark. when the engine isn't turning over, the power module is switched 'off' so there's no ground on pin 1.

on the power module, pin 1 (red-white wire) goes to the coil pin 1. pin 2 (black wire) is ground. pin 3 is the shield on the wire to pin 5. pin 4 is power (blue) from the coil pin 15 which in turn comes off the ignition switch. pin 5 is the control input from the ICU pin 16, a grey shielded wire.