[ManUtd4Life]

I have a 99 jeep grand cherokee laredo with 77,500 miles, My jeep worked until this morning, I tried to start the jeep but it kept cranking and cranking and just wont start. Here is what I have checked

1) My battery showed 12 V
2) My fuel tank is half full
3) i listned in the fuel tank and i did not hear my fuel pump turn on

After 2 hrs I gave up, and towed it to the shop. The shop guys are telling that my on board computer is not responding. So they cant diagnose the problem. I should mention that my jeep sat in huge thunder storm last night.

Could something be shorted or fried that stops the jeep from starting? how can I check for that?
where are the fuses?
could lightning fry my computer?
does the computer controls the fuel pump?
how much does a computer cost?

[Texas ZJ1]

Coil.


Hunter

[zaq123]

is it 4L WJ? Crankshaft Position Sensor

[rob_szma1212]

I had the same issue with mine and went a year without getting it solved. We replaced the Crankshaft Position Sensor and it worked for a little bit but then the problem came back. After a ton of research and long hours, we found out that it was a bad distributer. Even the shops we brought it too found the problem hard to find until they looked at that. It runs perfect ever since.

[eschell]

Here's the list we went through on the intermittent ignition loss on our 95 5.2 ZJ:

Coil.
Crankshaft position sensor.
PCM.
Automatic shutdown relay.
Camshaft position sensor - fixed ours.

If none of the above fix the problem, our dealer has had one instance of a bad wiring harness.

[Billyray]

If it says an error code of P0380 thats the crank position sensor FYI turn to the key the acc and the ignition 3 times and it will display in the odometer.