Error Code P0320

Jeep Liberty 02 stalled out twice on the way to work, no codes then on the way back, about the same place, say 10 minutes into driving it did it again. Each time the Tach went nuts, 0-5000 and it felt like the engine just shut off although I still had power sterring and brakes. The second time it threw a code, P0320.

This is a rebuilt engine, about 6K on it if that. I changed both the cam shaft sensor and crank shaft senor expecting that the engine rebuilder had used third party parts. In looking over the parts I pulled they are identical, same purple O-rings and Mopar part numbers in the same place, same font and size so pretty sure they are Mopar.

I cranked up the engine and I am still seeing the same code. I attempted to reset using OBD Armey and other apps but it would not reset them, wants you to buy the app. I have not pulled the battery cables or driven it. Before I do either I'd like some input as I don't want to get stuck on the side of the road again, on a Sunday night in the rain.

Well I went ahead and pulled the battery cables, left the car door open while I also changed the Idle Air Control unit and the code is gone. Upside, Jeep idle is much smoother. Drove it on secondary roads, max speed 50mph, for just under 20 miles and it's smooth with no codes showing or coming back. My concern is does this mean it's fixed or has it just not thrown the error yet because my stalls I was getting didn't happen until I drove halfway to work on the Interstate at 65-70MPH, then it stalled out. Waited a bit and I was able to drive the rest of the way in. Ditto for going home, halfway back it stalled on the Interstate, waited a few minutes and was able to continue home.

Probably won't drive it in tomorrow, Monday traffic always seems to be the worse.

I'm also thrown by the engine rebuild and would have thought a rebuilt engine would have new sensors. The two I pulled clearly look like Mopar parts so for one to go out in less than 6K miles doesn't sound right at all. If on the other hand they were original to the engine then they could have 100k, 150k, 200k on them and surprised a rebuilder would leave them in when they cost just $30+/-.

Sounds like the new IAC helped, but you do realize that the P0320 is a no No Crank Reference Signal at PCM module or potential crank sensor issue, wiring or senor itself ?
Engine rebuilder's generally will re-use your existing sensors, if they had to replace them all, they will add the new sensor costs to your bill !
What brand of crank sensor did you buy? Selecting Mopar sensors is always recommended.

LibertyTC said:

Sounds like the new IAC helped, but you do realize that the P0320 is a no No Crank Reference Signal at PCM module or potential crank sensor issue, wiring or senor itself ?
Engine rebuilder's generally will re-use your existing sensors, if they had to replace them all, they will add the new sensor costs to your bill !
What brand of crank sensor did you buy? Selecting Mopar sensors is always recommended.

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The Idle control was replaced because I bought it months ago after getting the rebuilt engine in and it was rough idling, I just had never put it in.

I only use Mopar sensors. I'll use third party parts for things like pads, filters, etc but never a sensor however the crankshaft sensors are no longer made so we will all be using third party sensors here soon.

Drove it in today anyway, drove fine, no codes or stalling. Hope going home is the same.

I agree With LibertyTC that this is probably a Crank Sensor Error itself or a wiring issue.

Could be a bad connector on the sensor or re-plugging the connectors on the PCM a few times may clean up a bad connection. Try trace the leads from the Crank Sensor to see if it is chaffing on motor/chassis any where.

Could also be a bad ground somewhere.

These sensors can fail sometimes when they get hot. Measure the resistance of the sensor at room temperature with an Ohm meter and check if the resistance changes while heating it up with a hair dryer.