erupert66

My son has a 1991 Jeep that he's had for a few months. died on the side of the road the other night. did some troubleshooting and no spark. checked and crank sensor wire wasn't bolted at fuel rail so it was next to the header and melted. here's the weird part - the sensor my son picked up is a round plug with 3 pins in triangle shape but his harness is not like that. maybe the PO changed part of hte harness? it's a bizzare thing as the VIN plates are original and peg it as a 1991 but there is a 1993 emissions sticker on the firewall. so, the crank sensor is an oval with 3 pins (pretty tiny compared to the round one) straight in a row. At the auto parts store, the couldn't find a jeep match but found something from another vehicle. I don't think that it's a good idea to use it and then not be able to return it if it doesn't work.

Anyone have ideas on what year this harness might be? It's a base cherokee (crank windows, manual locks, 4.0 auto)

nicksan

Have you tried splicing the wires together to see if it will start ?
Try these links:



http://www.1aauto.com/1991-92-jeep-c...FZKIaQodcCgDSw

http://www.rockauto.com/catalog/rafr...rttype=7196&ck[ID]=0&ck[idlist]=0&ck[viewcurrency]=USD&ck[PHP_SESSION_ID]=c0p3trveou9drqnii2u19iu8k3

cruiser54

What's the 10th digit in the VIN number?

94XJ4point04x4

Please do not slice Sensor wires...

nicksan

Whats the harm?
If you connect the wires back up like they were, then you can determine if the sensor is bad or not.

94XJ4point04x4

Signal wires are never supposed to be spliced. They use a low voltage reference.

nicksan

Because its adding resistance to the circuit?

94XJ4point04x4

Yes. The Computer is made to compensate for certain resistances in connectors and wires. The cps signal is very small because it is a hall effect sensor that uses a magnetic fields and and uses a very low signal from each teeth from the flywheel or flexplate. Each time a tooth passes it a small voltage is created. That is why in many cases where the cps may be at question for fault it is best to just replace it rather than test it. We use oscilloscopes to test them in a shop.