Went to the store today and when I parked my truck, before I turned it off, I sat for a minute w engine running, then the truck just died. Won't start or act like it's even trying to fire.

Got P1391 code. What should I try to trouble shoot?

I replaced the computer 3-4 years ago. Also replaced the fuel pump in similar time frame.

Thanks, Dan

 

This is a 360 4x4 automatic.

The only two times this truck has done this (just died) since I've owned it since 1997;
1st time - fuel pump (I dropped tank and replaced, all good),
2nd time computer controller died (I replaced it, all good, but not before dropping tank and replacing pump unnecessarily)

 

P1391 code is the loss of either you crankshaft sensor or camshaft. The crank sensor would be more likely the cause. Have you replace the transmission at anytime? Because the crank sensor wire is easy to pinch to ground. If you replace any sensors use Mopar parts.

 

Have never replaced the transmission. I'm going to find a mopar sensor and try that.

 

You will find the sensor on the passenger side on the rear of the motor.

 

It's a pain to change...... Need your arm with it's three elbows....

 

Well, I was just out in the driveway monkeying w this thing. Still no start and w the code. It took me about 6 tries w various extensions and wobbles and knuckled extensions to get one bolt off. What a pia that was.

I went to try to get the next one, towards the driver side and there isn't enough clearance for my socket. So I was about to go to the store to get an Allen socket for that other bolt. Before I did I decided to try to start it and it started right up... so, what now?

I don't know what happened, must have jostled a wire or something. I guess I will have intermittent problems till I replace that sensor.

This is the first time this has happened and first time for that code.

 

Check the connector, make sure it is clean, and plugged in good.

 

I got the mopar crank sensor this morning and put it in. It still won't start. I have fuel, pulled plug and was wet w fuel and I listened to the fuel pump in the tank turn on when the ignition switched on. While I had a plug pulled I cranked it over and saw that it was sparking when cranked.

I cleared the P1391 code, however I'm not sure if the code would be thrown while attempting to start it.

Should I replace the Cam sensor now?

 

I did a test with the voltmeter on the cam sensor, back probe on tan lead and I'm seeing the fluctuation between 0 and 5 volts when I crank it, so I think the cam sensor is good.

Would the ECM be bad but still turn the fuel pump on and spark etc?

I'm going to test the coil, maybe it's not hot.

Any suggestions?