WWDiesel wrote:
There seems to be a lot of failures or suspected failures of Crankshaft Position Sensors on our Jeep CRD's in the recent past.
So, I thought I would start a thread for everyone to list their failures so all on here could learn from it and know what to expect when it might happen to them!
Please post your symptoms and / or details if you have had a failure of the Crankshaft Position Sensor so all can learn from your experience.
Here is the sequence of events:
My wife tells me one day she came back to start her jeep which was already hot. It took a long time cranking but eventually fired up fine, with
no codes.
1wk later, same thing.
1wk later, Jeep wouldn't start at all hot. Let it cool and all was fine.
1wk later, it almost died on me while in a drive thru. It was like all the injectors quit firing for a quarter second, but afterwards kept running smooth and with no codes.
1wk later, while I was out of town, of course, it died on her at a stoplight. After cranking for a while it started up and drove fine. After getting to her destination, it wouldn't start at all and she had to get a ride home.
After reading jeepdan's saga, the first thing I suspected was the crankshaft position sensor. So I took it out and did the same heat gun test on it. It started out at 1100 ohms and steady, but after only about 30 seconds the resistance skyrocketed up to 40kohm and bounced around between there.
To remove the crank sensor, the best way is from under the passenger side. There is a small heatshield on the block, below the turbo, which protects the sensor from heat off the downpipe. Remove the two 10mm bolts holding it on and you can drop it out and see the sensor. An 8mm bolt holds the pigtail bracket to the engine, I had to remove that just to squeeze the plug locking tab. Then a 5mm allen will remove the sensor from the block, it sticks about 2 inches into the block and will come out oily.
I have the P0340 code on my Jeep right now. Over the weekend I put another Bosch CPS in it and I erased the codes. I drove it all weekend and each time I shut it down I checked the OBD and all was good until last night when it reappeared. I noticed that their is no 'heat shield' on this Jeep between it and the exhaust......could the heat be killing the sensor or possibly causing bad readings? I havent had any problems starting the Jeep at all whether it is warm or cold.