Random misfire code and RPMs dropped to zero

[Jackjack97]

I was driving down the road today and I was going around 45 when suddenly the Jeep felt like it down shifted where it jolted and the rpm gauge dropped to zero but almost imidiatly it came back up and was fine. It threw a random misfire code. I have a 1997 with 193k on it. It is a 4.0 with a 5spd manual. I have recently replaced distributor cap,rotor, spark plugs and spark plug wires. If any one could help me that would be great.

 

[CharlesHS]

Check the following:

The (3) 32 pin harness connectors that snap into the ECM; check the pins and clips for oxidation and ensure the harness connectors are snapped into the ECM firmly.
Check the wiring harness that is routed behind the valve cover that goes around the head stud to ensure its not rubbing on the stud. A bare wire can short to ground causing this problem.
You should also check the ground wires going to the block on the passenger side to the left of the oil filter; dirty or loose connections can cause issues similar to yours.

 

[Jackjack97]

Check the following:

The (3) 32 pin harness connectors that snap into the ECM; check the pins and clips for oxidation and ensure the harness connectors are snapped into the ECM firmly.
Check the wiring harness that is routed behind the valve cover that goes around the head stud to ensure its not rubbing on the stud. A bare wire can short to ground causing this problem.
You should also check the ground wires going to the block on the passenger side to the left of the oil filter; dirty or loose connections can cause issues similar to yours.

Okay I will check these things out thank you