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trans problems.

its840

NAXJA Forum User
Location
Louisville Ky
98 2wd 4.0

ok so heres the skinny.
i went to my moms house to flush that radiator. doing so i had the hose setting on the engine running.. prob like 20-30 minutes.. (i went inside and forgot about it) but anyways.
Afterwards, i take off down the road and i have a check engine light and it wont shift out of first gear. so i take it to the zone and they tell me its the tps sensor.
ok i dont have a clue how the TPS has anything to do with the trans.. it was running fine it just wouldnt shift. but what ever, so i change it.
Well now it will shift gears, but, 1st gear wont shift till i hit like 3200 RPM.. also 1,2 and 3rd gear i do not have any tourque convertor lockup. at 3000 rpm i take foot off gas and it goes straight to idle.
well i needed to get home. so i limped it home. on the highway at 70 mph it was driving fine. tourqe convertor was locked up like it should have been. but as soon as i got off highway same deal all over agian. hard shifts out of 1st and 2nd.
and yes it has trans fluid. but.. i changed fluid and filter like 10k ago.. but the fluid is not purdy pink anymore.. sorta a darker pink..
pretty much at this point i am a little stuck.
Thanks for any input!!


also is there any adjustments on the TPS??? like before i would have to give it 80% gas for it to kick down on the highway. now not even 20% and its kicking down gears. thanks.
 
Check the transmission valve cable. Its so easy a caveman can do it.. matter of fact there was a recent thread on it. Its best to see with the diagram. Someone will post it. If not search it.. also some of the sensors love water like cats.. the tps being the worst.
 
Throttle pressure cable adjustment: http://naxja.org/forum/showthread.php?t=1015963

On the AW4 equipped vehicles the TPS provides data to BOTH the PCM and TCU, so yes, it effects how the electronically controlled transmission operates.

When everything is operating correctly, you have to raise your rpms up to 4000-4500 to get shift from 1st to 2nd in 1-2.

When you say you changed the fluid and filter--drop the pan, replace the filter and add 3.5 quarts of fluid? That would leave about 9.5 to 10 quarts of old fluid in the transmission.

The TPS on the Renix era (87-90) are adjustable. 91+ it is strictly test and if out of spec replace.

Good luck.
 
ok i dont have a clue how the TPS has anything to do with the trans

Welcome to Naxja, we're happy to provide clues!

The throttle position sensor is one of the inputs to the trans computer so it knows when to shift. If its refusing to upshift until a really high rpm, then it may very well be a bad TPS telling the trans computer you've got it floored. What engine code did you get?

The TPS is notoriously easy to kill with water, usually it happens as a result of someone innocently attempting to pressure wash their engine. You tried unplugging it to see what happens? It can be tested with a voltmeter too.
 
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