1G Transmission relay

[Topcarparts]

Is there any transmission relay on 1g?where it is located?

 

[1990TSIAWDTALON]

Just solenoid valves in the tranny.

 

[Bleakley]

Why do you ask?
That’s a good question.

 

[Topcarparts]

I think i have a problem on relay..but im not sure to find it..

 

[Topcarparts]

Just solenoid valves in the tranny.

U mean sir 1990 91 eclipse no tranny relay or AT CONTROL relay?just solinoid valve inside tranny?

 

[1990TSIAWDTALON]

Yes. My 92 auto has no relays. Manual shift Park, Reverse, Neutral and Drive. The other gears are all controlled via a transmission computer (TCU) and it runs 4 solenoids inside the transmission for forward gear selection and line pressure. I have never seen a 1990 auto trans car, not that they weren't made, but I have never heard of or seen one. They started in 91.

 

[Topcarparts]

On papers mine is 90..but i think this 91 bcoz it has abs.turbo N.A awd.

My problem is my transmission i think is bad.
I cant accelerate much.i need to step on gas pedal before it accelerate.
Like im in full stop the put it on D. The car wont move..i need to step on yhe gas pedel to move..

 

[Topcarparts]

Now im going to focus on TCU.. but somebody pls tell me were is the location of this TCU?
1G

 

[1990TSIAWDTALON]

Your transmission is in what is called "Limp" mode. You can try to disconnect the battery for a few minutes and then re-connect it, possibly resetting the transmission computer, and getting it out of Limp mode but it doesn't always work. The transmission will still move but it is stuck in 3rd gear, isn't it? There are several things that can put it into Limp mode, mine was the Vehicle Speed Sensor acting up. It is built into the speedometer so it isn't really serviceable.
You will need to source a different TCU (transmission control unit) or have yours repaired, if there is anyone around you that can look at the capacitors and circuitry in the computer.
The TCU is located behind the radio and under the ECU. You can access the TCU from the passenger and drivers side, at the front of the console. Remove the side panels near the firewall and you should see it. It will sit flat, if I remember correctly, and is mounted with 3 10mm bolts I believe. It will have either 2 or 3 connectors going to it that you will have to remove. They are for the power, input and output of the TCU.
Hope this was helpful!
Marty

 

[Topcarparts]

Wow tnx for this sir.. ill try to repair it my self.. and yes i do the remove battery reset..it work for a while only..

 

[1990TSIAWDTALON]

It has to be one of the inputs that feed to the TCU that is throwing it into Limp if doing the battery trick helped for a bit. The trans has pulse generators, speed sensor, tps inputs and I am not sure of any others, but if any of those are not sending the correct information to the TCU, the transmission will revert back to Limp mode.
Good luck my friend!
Marty

 

[Topcarparts]

Let me check also the tps..
Bcoz when i reset the batt it shifts fast..then downshift is not smooth..uestuon is how do i calibrate or what is the correct position of the tps?

 

[Topcarparts]

The speed sensor sir i think its fine..bcoz my speedometer is working fine also the milage guage

 

[1990TSIAWDTALON]

Check the TPS with the key on, .63+ volts dc at zero throttle position on the signal wire. Loosen the TPS hold down bolts and twist it to achieve the correct voltage. I replace those hard to get to bolts with allen head screws for easier access if I need to adjust it. I have used a wire tap and a digital multimeter to set it.

 

[1990TSIAWDTALON]

You CAN unhook the outputs and make your own shift box to make it shift if needed but I would spend the USD and get a SmartShift 100.1 TCU and get rid of the factory TCU.
See here.....
http://www.forcedfour.com/smart100_1.htm

 

[Topcarparts]

But sir can u tel me or atleast photo which is the correct adjustment of TPS?

i think TPS is working but maybe not in the right position

 

[Topcarparts]

Sir my TCU part no. MD750092 then i found out a surplus part no. MD750094 then i put to my 1g.. it runs and shifts..

Now my question is.. whats the difference of this two tcu?
i open it up both TCU. Mine and from surplus.. there is a slight difference.but i dont know what for.