Jus wanting to get some clarification on cel code 1391. 2001 4X4 5.9L. truck seems like its running good after plenum fix and new o2 sensor. take it for a 20 minute trip to a restaurant last night. put her in reverse, back in to my spot, rpm's start jumping 600-1000 over and over. come out after dinner and seems fine. Drive her back home, pull in the drive way and put her in park, same thing starts happening. this time cel comes on. Read the code 1391, camshaft sensor/crank shaft sensor. Truck seemed fine again this morning before I went to work.

I've done alot of research on this cel to day but the posts I've found have mostly been unanswered. Anyone been through this and replaced the camshaft sensor and fixed the issue?

 

Trouble is, those sensors are hard to test....... you can ohm them out, but, that only tells a part of the story. Trying to figger out which one is bad is the fun part...... so far, the only way I have seen that is a 90% likely fix, is to replace both with dealership parts. And they are not exactly cheap. May want to check and make sure you didn't pinch any wires doing the plenum.

 

I'd lean more towards crank sensor, but either way, make sure you didn't knock one of the connectors loose or damage the wires for either sensor.

 

Gonna hope for the loose connection fix if parts are too expensive it will surely hamper me from getting my exhaust and tuner. cant believe my wife is still gonna let me get them considering we just found out today we have to shell out 5k for my kids to get braces.

 

Checked all the connections and wires. Everything seems to be in order. Cleared the cel and took it for a 30 minute drive with no issues. WTF moment I guess

 

At least it was cheap.

 

I just recently had the 1391 on mine and it turned out to be the crank sensor I had already replaced was bad.