Hi all, wondering if someone could help me out, i have a 98 Dakota with a 3.9, about a month and a half ago the original motor finally let go and put 2 rods through the oil pan, so i bought a new (used) motor and put it in, when i pulled the old motor out i left the trans connected to motor and pulled both out took trans off and installed it on new motor, everything seemed fine until i started it, it had this noise that to me sounded like the inspection plate was being rubbed by torque converter, and the truck would not shift gears 2nd gear only or rev above 3000 rpm and was throwing code for overdrive solenoid so i bought a new overdrive and tcc solenoids and installed with brand new Mopar atf+4 fluid started truck same thing loud noise and solenoid code but now had new code of gov pressure sensor or gov pressure too low, fearing i had damaged the trans pump bolting it up to new engine i bought a rebuilt pump and installed and also replaced gov pressure solenoid and sensor, reinstalled trans replaced fluid and started, now there's no noise truck sounds great but trans still stuck in second only and won't rev above 3000 with same codes, i can clear the codes and they instantly come right back..... Any ideas? Thanks

 

Did you pinch/short/damage the transmission harness during the trans swap? That's what it sounds like to me. Trace the harness back, I bet it's pinched or cut between the transmission case and the body, or along the driver side exhaust.

 

That actually was gonna be my next step, i do not think i pinched or pulled, binded, scraped and or cut the harness but anything i guess is possible so i will be diving into that next. Man if i didn't love this little old truck I'd just get rid of it but for being almost a quarter of a century old it still rides like a Cadillac lol

 

Ok so i pulled the harness and to my surprise it was in bad shape to put it nicely, the 8 pin connector had 4 bare wires right there at the plug all wrapped around each other, the plug right under the 8 pin that has 3 wires going to it were all bare approx 2 to 3 inches from the plug so i fixed the wires by cutting and soldering back after putting heat shrink on the wires and doubled up on all the heat shrink then electrical tape followed wire harness loom then more electrical tape then i found on my 02 sensor harness b1s1 the 02 sensor has 4 wires but there were 7 in that harness 3 had been cut and just stuffed back in wire harness loom, have no idea where they w went out what they plugged into, i know i didn't cut them and truck shifted fine before engine change so i terminated the ends with butt connectors and taped, started truck and truck is still in limp mode BUT no tcc or overdrive solenoid code, just the 1742 i think, the gov input voltage to low or to high, was reading somewhere 1 of the 02 sensors could cause this code, one place said the pre cat 02 sensor and another said post cat 02 sensor, any idea which one i should check? Or what else i could do? I am going to recheck my soldering to make sure one maybe didn't hold but i think i did feel it shift into od when i test drive it but still won't go past 3000 rpm or 50mph

 

Did you adjust the TV valve after you got everything back together? Clear the old codes they don't all go away after you fix something. 1742? I think you mean 1740. Will the engine rev past 3K in neutral?

 

Not sure how to adjust the cable, won't rev past 3000 rpm in any selection including Park and neutral unless i reset the pcm then it will for about a second until the codes come back. I will screenshot the exact codes and post

 

 

All of those are relating to the 5 volt bus for various sensors. Check and see what voltage you are getting on the 5 volt feed to your O2 sensor. Go from there.