I have a 02 2500HD 8.1 and it has been shutting off while driving lately. I have to pull over and turn the key off and most of the time it will start back up. Sometimes I have to do this 2 or 3 times to get it to start again. It set one check engine light after I cranked on it for about a minute. It was for the crank position sensor. It has not set a check engine light since then. Anyone else have this happen?

Thanks
Chad

 

Sounds like the cranks sensor need replaced. Several have had this problem and it don't always though code.

 

Someone told me that I would have to reflash the computer when I installed the crank position sensor. Is that true?

 

Yes, I believe you do have to perform a crank relearn procedure after replacing it.
I hear it is a pain in the *** to R&R the sensor.

 

Ya its fun....i did mine with the intake and heads off.....I cant imagine doing it with the motor all together. Your going to need some mirrors and a good flash light to see what your doing. Its only a 10mm holding it in but some times the ****** sensor breaks taking it out. Id recommend being patient and wiggle it back and forth while pulling up as to not snap it. Have fun

Alex

 

What a PAIN!!! I did change it with everything together but it took a little while. I managed to break the sensor even with the block. Luckily the 3 metal wires were sticking up and I could lock vise grips on them. Once I got them locked on I pryed against a breaker bar and it popped out. I was thinking for a while that it was going to mean pulling the intake and head.

Truck started and seems to run fine without doing a crank relearn. Hopefully this fixed the problem.

 

HAHA!! sorry thats not funny really. Mine was doing the same thing it is definatly the crank sensor - I had mine at the dealership for 4 days and they couldnt get it out, so i told them to give me the new sensor and i would do it myself. So here is what i did....

First it is located in the most f-ed spot - back of the block. you need a mechanics mirror and some PB Blaster - spray around where the senor goes into the block-depening on the mileage it will be tough to get out...

Now the fun begins - is used an old detroit diesel distributer tool which fit perfectly around the base of the sensor and slowly pryed it out. You have to be carefull though that you dont break the sensor housing or you will have to tear it down to the block. All this was done from underneath the truck and using the mechanics mirror to align the tool up with the base of the sensor. A regular screwdriver will not work very well for this.

It definatly isnt fun, but it can be done, it took me 2 hours to get the old on out and the new one in...and when putting the new one in be sure to oil the **** out of the o-ring. And when pushing the new one in you will know its in all the way when it "pops" into place (you wil feel the o-ring set into the block)

And there is no need for tunning the new sensor - the computer will relearn the new sensor fairly quickly..

I hope this helps..

Todd

 

no just disconnect the battery before you start and obviously reconnect after you are done. Mine never needed anything more...

 

I had the battery disconnected and I have driven about 50 miles and things seem to be ok for now. But we will see, it was random when it would shut off. Yeah it was a pain to get out but it only took 2 hours. I hope to never do it again though!!!

 

so you already changed it out