1991 Suburban acts like out of gas or fuel pump

[dyeager535]

You can probably trace out roughly where or what it was.

I luckily haven't had to deal with that wiring in awhile, I want to think the distributor wiring is one piece...if it was the wiring that was damaged, a distributor wouldn't have fixed it.

That therefore indicates to me that whatever the ECM B fuse feeds in the distributor, was shorted. The ignition module or coil are the only things I can imagine that could short out inside the distributor.

 

[GaBnn3]

I understand and agree with the electrical theory. But, I obtained the wiring manual from a source herein. The ECM B fuse feeds a single circuit #440 from the fuse box through the under-hood engine wiring harness, to a 4-way splitter at the upper rear of the engine numbered S140 in the manual. One lead then goes to the oil pressure switch, one goes to the fuel pump relay and the other two go back through the firewall to terminals B1 and C16 on the ECM. In a no-start condition without SES light, the manual states that the remedy is to find the short in the circuit with the blown fuse. Using a multi-meter I verified a short between the fuse socket and ground. I was ready to dig into the engine wiring harness, but am sure glad I didn't. It's a moot point now. But, could a short on something connected to an output from the ECM cause a current draw through B1 and/or C16 that would cause the ECM B fuse to blow? Some who posted thought the distributor could be the problem. But, using the manual I can't make the connection. Which speaks, no doubt, to my inability to make a connection rather than it's non-inclusion someplace. Thanks to all who contributed.

 

[Wes Harden]

Repair manuals are full of miss prints and wrong paths.
One of My Ford factory instructors loved design an exercise around a trouble tree that was total BS in the factory manual. There were many lessons like that.


I think the shop probably just started unplugging items till the fuse didn't blow

 

[dyeager535]

I'd agree that's odd. I would look at the distributor wiring in the manual and figure out how that is powered.

I would have guessed a short after the ECM would have fried it.

 

[bigjimmy82]

... and check that you don’t have a larger ECM-B fuse now.

 

[Blue85]

Or is the problem intermittent and they disturbed that wiring while messing with the dizzy? (i.e. the problem may come back)