auto tranny issues 92 4door

[knightwriter]

so after a 2 hr highway drive and an overnight cool down period, the tranny in my 92' auto is acting strange. the lights for D4 don't light up at all anymore, and it feels like i am starting in 3rd gear when i put it in D3 (lights still work for D3,D2,D1). i can shift to 1st manually and pop it up as needed, but than the car won't downshift on its own. the only way to downshift is to pop it into D2 while moving slowly before a stop.

also, every time i put it in park, the shift lock engages and won't release until i use my key to unlock it. I noticed a burning smell when i first left my driveway and was in my neighborhood (burning sensor??), and ever since than, the shift lock has been acting this way. very strange. otherwise the tranny seems strong, but just not acting right which makes me believe a sensor has burned up or something. any suggestions??

[RUGER 2.2L]

Hmmm sounds like you might be having a problem with the TCU (transmission control unit). I assume your gears aren't slipping or anything so it is probably not a mechanical problem. I guess the burning smell could have been your TCU frying. I would wait for some more insight from other members, but that is what it sounds like to me. If you track the problem down to the tcu, you can pick up one up at a junkyard for pretty cheap just fyi.

[stretch JDM]

to me it sounds like your TCU has gone bad. its located under the passenger side floor board next to the fire wall. it the smaller box. open it up and look for bad spots. as you said it will have a odd smell. you can find one at the local jy. you must stay in your year range. 90-91 or 92-93. good luck and i have been there before .

[Ratty]

+3 on the TCU frying. Sounds like the same thing my '90 EX did.

You can just sniff the TCU, cold or hot. If it smells burnt, it probably is. Pull the TCU out from it's mount but leave the harness connected, run the car for a bit and then see if the TCU gets hot, if it's too hot to touch, get a new one.

You can try rebuilding it but that's no guarantee. The main chip in mine burnt. The replacement I won on E-Bay was only $20 shipped... cheaper than shipping on the replacement parts I bought for the old computer.

A 90 to 93 TCU is a direct replacement, but a 94-up will work the transmission just fine, but will blink the D4 light.

The Oki built units seem to be the one's that fail... can't prove that yet though. My replacement was made by a different company and the circuit board is totally different, sharing only the main chip with the old OKI board.

[knightwriter]

thanks for all the info. does anyone have a spare TCU laying around? or does anyone know of any good ebay parts dealers? or maybe you can direct me to a good JY that will have one. I am in the washington DC metro area. thanks again

[Meangreen]

thanks for all the info. does anyone have a spare TCU laying around? or does anyone know of any good ebay parts dealers? or maybe you can direct me to a good JY that will have one. I am in the washington DC metro area. thanks again

I have two of them. pm me

[knightwriter]

I have two of them. pm me

iam very interested meangreen. i can't figure out how to PM you. send me your email or just email me at *deleted*

[deevergote]

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