My 2001 Dakota blew the timming chain cover gasket, dumped all of the coolent into the oil pan, blew a head gasket, hydro-locked one piston, which also cracked. So I found a used 4.7 at a recking yard. The replacement engine is two years newer and is suppose to be from the same type. I got the engine's all swapped out and now it will not idle, barley runs, when it does it is really rough. The only trouble code I get is P-1931. The problem is an intermitten signal from the crank and or cam sensor. I pulled the senseors from the old engine and installed them in the replacement engine and it still does the same thing with the same codes.

Any ideas where to look? Any one had this error code?

Thanks.

Dru.

 

Did you reset the pcm? There could be some problems with that.

 

Other then pulling the battery terminals, no. I have reste the OBDII with a code reader though.

Dru.

 

I see you wrote this back in Jan. and it's now April...but I'll give it shot. My truck/motor is 2000 4.7 and I got a "junk yard" motor which was a 2003 with 20k on it. Well, they did the swap and found out LATER that the 03 is NOT compatable with a 2000 (I believe he said the 2001 also). Something with the computer plug, one is a four prong verses a three. Something else he said was with the timing...didn't match my 2000 motor. Basically, I was told he could not do it because of the years had changed after 2001 for the 4.7 . I ended up buying a remanuf. 4.7 for $2400.00 that came with a warranty, the same price for the 2003 "junk yard" motor with no warranty. THAT'S ANOTHER STORY!
stu

 

have heard about motors not matching up on plugs. may have to sinc cam and crank sensor.