Hello , I'm new to the forum and I need help . My truck keeps having problems with the crankshaft position sensor . I got the truck from a friend who started replacing the clutch . He broke the original CPS , and I got it after he had reinstalled the transmission . I finished the install by reattaching the driveshaft , cross member , and replaced the clutch slave and master cylinder which he also broke . Unaware of the pickiness of dodge on aftermarket parts I purchased a CPS and installed it . Naturally it started but it was cutting out and acting like it was running on 2 to 3 cylinders . So after researching the issue I tried to order a new CPS from Dodge , unfortunately they no longer carry that part . So I did more research and found out that the original supplier was NTK/NGK , the spark plug people . I ordered one from them and the truck ran perfect , for 24 hours , then it died and I had to have it towed back to the house . And of course as soon as I it home it fired up and ran perfectly until the next time I got more than 5 miles away from the house . Had it towed home and fortunately the CPS from NGK was under warranty so they replaced it free of charge , so I'm currently getting ready to install the 3rd CPS . If this one doesn't work , where do you get a replacement that will work ? By the way all three of the replacement CPS are different lengths by 100 to 300 thousands of an inch . Any information about this issue will be greatly appreciated .

 

You can sometimes get lucky, and search on the part number for the Mopar CPS, and find them in places like amazon, or ebay, just make sure it is a GENUINE mopar part......

 

Thank you , would you happen to have access to the original part number

 

I just look 'em up on any Mopar site. And it's likely the same sensor for a variety of vehicles. (essentially, anything that used the 5.2 or 5.9 engine, it's possible the one for the 3.9 is different, but, I don't know.)

 

your note about the length of sensor is RELEVENT. The manual CPS is shorter than the automatic CPS - the flywheel diameter is larger than the flexplate diameter. Likewise, the 3.9 uses an alternating double-single-double-single pattern every 60 degrees, while a V8 uses single openings every 45 degrees. A "lazy" CPS will be much more obvious on a 3.9 .

Per RockAuto interchange, M/T CKP is 56027871 and A/T CKP is 56027870

 

What is driving me insane is the truck will start and run like a sewing machine , till I get between 3 and 6 miles from the house . Then it loses power , starts popping back through the throttle body , and eventually dies . When I restart it, it sounds like it's running on 2 to 3 cylinders and if you touch the accelerator pedal it dies . And it will stay like this for 1 to 3 hours until the tow truck shows up and haules it back to the house . Then when I restart it , it initially runs rough for about 5 to 10 seconds , then it smothes out and runs like a sewing machine again . When I get my check on the 3rd I'm going to try replacing the pickup coil , ignition coil , distributor cap and rotor , wish me luck .

 

Any codes??? How old are the O2 sensors?

 

I have no idea , a friend gave me the truck to use . He bought it and drove it for 3 weeks until the clutch went out . He replaced the clutch and towed it to my house for me to finish installing the driveshaft , CPS , and a new clutch slave and master cylinder . Since then it hasn't been driveable because every time I get 3 to 5 miles away from the house I have to have it towed home . No check engine light at all .

 

What brand crank sensor?? These trucks really don't like the aftermarket fellers....

 

have you checked fuel pressure ? i have had 2 fuel pumps die on me with those same symptoms id get just out of town and it would lean pop out intake and stall and take 20 min or so tell pump would run again