Transmission not shifting well. HELP PLEASE

[mooker82]

I just changed my coolant, thermostat, PHH and took off to eat some dinner and see if the Cruiser ran cooler. Cruiser was doing fine on the way there. I was driving with OD off to get the RPM's up to see if I could replicate my past overheating issues. No overheating. I then head up the interstate at speeds around 65-70mph OD on and cruise control on. Doing fine. Coming back home up the interstate I started to climb a hill and no downshift. Press the gas more and no downshift. It felt sluggish and would not hold speed going up the hill. No check engine lights came on. It will not drop gears for some reason. Any ideas where to start. Its a 97 with 285's.

 

[Gumby]

Didja put your transmission dipstick back in?

 

[IdahoDoug]

Did you get the engine wet in the process - flushing and overspray, etc? If so, open the hood for maximum drying airflow with a hot engine. Sounds like a connector is wet. Please tell me you didn't also decide to hose down or clean the engine...?....

DougM

 

[mooker82]

Dipstick is back in. Transmission fluid level is right in between the two top marks when it is hot. Engine got wet during flusing but that was over 8 hours ago. I did put a bag on the distributor cap to keep water away. Just got back from more trouble shooting and will add the following info.

Transmission shifts into and out of gears normally. It will not drop a gear to accelerate once it is in overdrive. Once speeds get down it will go back into what gear it should be in.

Took it out a while ago and it operated normally. Drove for a little while longer and it began doing it again. It appears to do it when it has been operating for a while and is hot.

 

[miked]

you guys know that wire harness that runs right under the PHH? ya know, the one you yank and bend down out of the way to get your little 1/4" 8mm socket drive on so can tighten the inner clamp?
what exactly does that connect to anyways?

just read your last post, this sounds very odd.

 

[miked]

i have to ask, what makes the tranny kick down when you give it more pedal?

vacume?
cable pull?
tps?

i've seen all three used as a indicator that the engine is under heavy load and the tran should down shift. my tacoma used the cable to tell the tranny how HARD to shift, not when. what does the 80 use to tell the tran when to shift?

 

[mooker82]

More testing and it now appears to do it just randomly(not dependent on temp). Also it will not drop other gears sometimes (not just overdrive). Only other thing that I have done different than normal is I put in $15 of regular gas and not premium that I normally run today. Coolant was flushed with Prestone Green which was what was in it before. Added bottle of Redline Water Wetter. OEM thermostat replaced. OEM radiator cap.

Bad gas?

 

[Rich]

you guys know that wire harness that runs right under the PHH? ya know, the one you yank and bend down out of the way to get your little 1/4" 8mm socket drive on so can tighten the inner clamp?
what exactly does that connect to anyways?...

Transmission.

 

[elmariachi]

Transmission.

That was my thought....that maybe you jiggled that harness connection and stirred up some voodoo. I'd be crawling back in there and checking that first.

 

[mooker82]

Just got out from under it a while ago and the harness is as tight as ever. It was not wet either. Test drove it and still the same problem.

 

[mooker82]

One more test drive before bed. Filled rest of tank with Premium from the gas station that I always buy from. Drove around for 30-45min. Still struggling around 2000 rpm's. Downshifts fine sometimes then others just chugs away around 2000-2200 rpms. Appears to be more random that what I thought earlier. Does this sometimes hot and sometimes cold. My girl thinks Im a little OCD about the cruiser. She asked if I would spend all day with her if she was sick. Well back at it tommorow morning before work to try and get this solved.

 

[IdahoDoug]

Open that lower connector up, spray some air in it, then fire some WD40 in it and slap it back together.

DougM

 

[mooker82]

Just spent a few more hours messing with this. Checked all connectors and they are good. Cleaned all the connectors as well. Added fuel treatment just to see if that helps any. Reset the ECU. So far no changes at all. Noticed it seems to not want to shift or get above 2000 rpms after I lightly apply the brakes. It also feels like sometimes the vehichle is not recongnizing the fact that the pedal is floored. Idle is around 800 with AC off and 1000-1100 with AC on. This seems a little high. TPS adjustment maybe?

 

[powderpig]

Remove the TPS connector and make sure it is had no fluid in it. Also when the engine gets wet I usually remove the TPS, Idle air control, air mass or air flow connectors and blow with air. These may be your culprit. You did not remove any of the cable to the Throttle body did you, if you did then check the throttle kick down cable. last but not least, check the carpet under the throttle to see if it has bunched up and not allowing full throttle movement (biggest low power complaint and easy fix). It also sounds like you unhooked and rehooked the connectors under the LHH, or am Not reading your post right. If not do this. later robbie

 

[mooker82]

Got out today and adjusted the kickdown and TPS sensor and boom...no more problems. Not sure which adjustment fixed it as I played with both before a test drive. Thanks for all the help.

 

[tarbe]

Whew! Gotta love those cheap fixes

 

[mooker82]

Yeah. All I could see is $$$$ when this first happened. I remember thinking these things have bulletproof transmissions right? Well its day 2 after the fix and all is normal it seems. Got all the belts and fan clutch put in recharged the AC and am enjoying the ice cold AC.