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Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
Originally Posted by Dan Larson
I wasn't sure what the cause might be. I did replace the coil pack which cleared all of the misfire issues. After clearing codes and restarting the vehicle I am getting P1391 loss of camshaft crank. Also the engine will make intermittent knocking sounds (video attached). I am next looking to replace the cam sensor and if that doesn't resolve the issue going back and replacing the crank position sensor. Can you recommend any other steps?
Other than check the fuel pressure, that sounds like the plan I would follow. Sometimes it's not too good at distinguishing between the cam and crank sensor. If you never changed the cam sensor, well, you'll get a new one out of the deal. Just be careful to drop it in the same way it came out. I assume the firing order has been checked? I would not run it too much like that if you can help it to avoid damaging the new coils.
Maybe try to peek up around the crank sensor and see if the wires or the throttle cable is resting on the back side of the sensor, that might interfere the magnetic pickup. Post back and let us know how it turns out.
A P1391 can be either the cam or crank sensor signal. If it's still running, I'd suggest it's the cam sensor since that's used to sync the injector pulse. And yeah, it looks like the coil pack is toast. Best to check the wiring first.
No, I've been hanging out in the XJ section and keeping my eyes on the impeachment debacle, and that's all I'm going to admit to. My sister-in-law passed away last week so there's that too. The Zebra should be back on the road next week, hopefully. We got nothing from Melling but a new pump, but Maabco rebuilt the motor for $350. The Rotella oil actually saved the crank, but the bearings were toast. They asked why the engine was so rusty and we told them it's been sitting outside with the head off for over 3 months! What do you expect for Central New York? It was still in the truck with the hood on it, but just the moisture got to it. Rain splashing on the ground got the bottom wet with the pan off.
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
Originally Posted by dave1123
No, I've been hanging out in the XJ section and keeping my eyes on the impeachment debacle, and that's all I'm going to admit to. My sister-in-law passed away last week so there's that too. The Zebra should be back on the road next week, hopefully. We got nothing from Melling but a new pump, but Maabco rebuilt the motor for $350. The Rotella oil actually saved the crank, but the bearings were toast. They asked why the engine was so rusty and we told them it's been sitting outside with the head off for over 3 months! What do you expect for Central New York? It was still in the truck with the hood on it, but just the moisture got to it. Rain splashing on the ground got the bottom wet with the pan off.
Sorry about the off topic, Dan.
Apologies too for hijacking, but Dave I wonder if your mechanic did you the favor of installing a high volume pump, and it broke because it couldn't pump enough. That is a known problem to my knowledge. I would inspect and make sure the new one is OE.
Apologies too for hijacking, but Dave I wonder if your mechanic did you the favor of installing a high volume pump, and it broke because it couldn't pump enough. That is a known problem to my knowledge. I would inspect and make sure the new one is OE.
You gentlemen are fine. I appreciate the help you both have provided. Side note I took my 19 year old's word when they said the ATF was at a good level. I double checked and found it to be 2 quarts low.... Not happy about that and likely contributed to the noise and gear slipping when I was in reverse.
Since I'm just replacing the Cam sensor and not taking the camshaft synchronizer out would I still need to make sure the 1st cylinder is on the compression stroke when its reinstalled?
If all you did was take out the 2 screws and replaced the sensor, you're still good. If you removed the drive, it has to be retimed.
I replaced the cam sensor and fired the jeep up again. Still making the same noises that are depicted in the previous video. I am guessing next step would be to replace the crank sensor again?
Since replacing the Cam Sensor. I attached the negative terminal back on the battery and had the codes cleared. Ran for several minutes and have the P1391 Loss of Camshaft crank, P0353 Ignition coil C circuit malfunction & P0352 Ignition Coil B circuit malfunction. During this time there was a faint smoke coming from the rear of the engine compartment. As a precaution I took it out of my garage to the street and found a puddle of ATF on the ground. Also my oil pressure gauge was reading 0. I replaced the oil pressure sensor within the last year.
12-12-2019, 10:19 AM
