Crank no start troubleshooting [FIXED]

[rhekman]

I drove my 95 to work this morning with no issue, then suddenly had a crank, no start condition at lunch. Good crank speed, dash lights up, check engine light on, then off during cranking. 1/4 tank of gas, hear the pump at key on, with a good spurt from the fuel rail Schrader valve.

Now after a quick tow home, I unplugged the battery for 10 minutes, and bam, it started right up. But now the tach is dead on the dash.

Has anyone seen similar symptoms before? I'm literally getting a ride right now to pick up a loaner, but I'm going to do more troubleshooting when I get home. Plan to start with crank position sensor, pcm harness, etc.

 

[franklin2]

Tach hooks directly to the PCM. If it will let you, I think I would try to pull some codes and see what it says.

 

[rhekman]

Tach hooks directly to the PCM. If it will let you, I think I would try to pull some codes and see what it says.

LOL, I wish I had plugged in my scanner just to see what the PCM was doing.


Turns out it I was struck by a golden BB.

Thankfully it was a quick and free fix after visual inspection.


I started by looking over fuses in the distribution box, then I crawled under the front bumper to look over the harness for the Crank Position Sensor.


Amazingly, a wire twist tie had landed on the sensor bracket, hooked itself there, and had a tail scraping around the trigger wheel right at the sensor gap. Removed that bit of debris (or "duh-briss" to quote VGG), and the truck started right up and ran normally. Tach is also functioning properly again.


I THINK that piece of wire was from a road-side fix about two years ago when the little plastic link bar broke on my throttle body and I temporarily wired it together to get home. Part of my fix disappeared by the time I got home and made a permanent fix with epoxy. Where that little bit of wire went didn't even cross my mind.