Mechanics

4.0 TURNS OVER NO SPARK

2000 Jeep Wrangler

Engine Performance problem
2000 Jeep Wrangler 6 cyl Four Wheel Drive Automatic 97000 miles

My son and I replaced the 4.0 engine in his 2000 Wrangler Sport . It was running when we parked it to swap the engine with a rebuilt. With the new engine it turns over but does not start. There is fuel. There is no fire from the No. 1 plug wire. It was showing No bus on the odometer, fuel gauge, and volt gauge were inoperable. I switched a couple of the relays (ASD and something else) and the no bus went away, gauges started working. I switched the relays back and the "no bus did not return, gauges continued to function. However the engine still turns over, but will not start. It has a new coil pack. There is small relay that is grounded to the block just above the oil filter. The wire kept coming out of the relay plug so I put a new terminal on it and cleaned the ground connection.


http://www.2carpros.com/forum/automotive_pictures/559432_Right_side_of_engine_off_of_internet_site_1.jpg

I feel like we have not put a wire or connection, something, back like it belongs. Any ideas? Thank you.
Avatar
Reagan78757
August 8, 2010.




Hi Reagan78757, Welcome to 2carpros and TY for the donation

Lets start by inspecting and testing the crankshaft position positioning sensor-this is the one that tells the computer what plug to fire-let me know

Tiny
Rasmataz
Aug 8, 2010.
It turned out to be the Crank Position Sensor. Upon re-installation of engine, we apparently bumped the CPS wire, partially severing the wire next to the sensor. New sensor and it fired right up. Thank you!
AD

Tiny
Reagan78757
Aug 11, 2010.

AD