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P1870 code help

Discussion in 'General Chevy & GM Tech Questions' started by daddytech, Jun 14, 2009.

  1. daddytech

    daddytech Epic Member 5+ Years 500 Posts

    I took a little trip to Memphis this past weekend to pick up a motor for my sons 88 S-10. I was pulling my car trailer with an engine hoist, and the 350 4 bolt main block i was trading even for the complete running 2.8 replacement motor. by the time i made it from Nashville to Jackson I had the SES light pop on. the truck started to shift really sloppy after that and almost like i was losing power the further along i went with it. The gentleman i was doing the motor swap with just happened to have a code reader at his house and was nice enough to check the codes for me and there was two instances of the P1870 code in the computer.

    I had him clear the codes for me and i was able to drive back with the new motor for my son's truck at speeds of 70- 75 where with the codes registered in the computer i could only go 55 to 60 and felt like the truck was really straining to do that. After the codes were cleared it was acting right again and i didn't have any more problems.

    When i left the guy's house i checked the fluid because the code refered to fluid level and the torqe converter clutch solenoid both. turns out the fluid is about a quart over full. I made it back to Nashville with it, running 70-75 with no problems but it's REALLY weak all of a sudden.

    I am starting to realize that i will probably have to switch out the TCC soilenoid but not sure how easy it is to get to. I have found replacement parts for around $25.00 but not sure where it's located or how to get to it. Anyone able to give me a helpful hint or guide to it? I am not a transmission man by any stretch , usually if the transmission gets weak, I just replace it. this time i want to be sure that i just don't keep driving it this way. getting ready to make the fluid levels right. I put in a drain plug the first time i changed out the trans fluid so i can control how much i take out of it but any help with the TCC module would be greatly appreciated.

    thanks in advance
  2. Jimmiee

    Jimmiee Epic Member 5+ Years 1000 Posts

    It's probably NOT the TCC solenoid. If it were it would set a circuit code. The P1870 is a performance code. Like I mentioned in another thread the most likely cause is a worn TCC regulator bore. Sonnax makes the reamer but the reamer is expensive. Rather than buy a tool you will never use again consider a reman valve body. Check out VBX reman valve bodies on the web.

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