Runehang

Hi! My Automatic trans will not take off i 1. gir. Nothing happens when i pull the throttle down. The other gears i perfect. I am wondering if a flush of the transmission can help. I have tried changing oil and filter, but it did not help. Anyone that have experience with flusing?

Rusty Spokes

Sounds like the gearbox is in "fail safe" mode. Is the PRND321 selector indicator on the dash showing each gear as you move the shift lever? Is it completely illuminated?

Could be several solutions..a bad transmission (the worst) to a corroded connection to the multi-function switch (easy) or #15 fuse. Lots of possibilities. More information would be helpful.

Try checking fuse 15 and disconnecting the battery for a while if the PRND321 is all illuminated.

Runehang

Thank you for the answer!
The selector i normal when i start, but after driving for 10 min or so it lid up! If i then turn of the engine and start again its normal again. The trans act great exept for that 1. Gear not working

Rusty Spokes

So 1st gear is not working? All other gears are working? Will 1st gear work if you select 1st?

The PRN321 lighting up is an error with the electronic controls (or a fried gearbox). The fact if you restart the car the PRN321 goes back to normal would indicate the transmission could use a service..ATF/filter..it could be low on ATF..or a poor connection at the multi-function switch or the MFS is not getting a good 12v (very typical problem as the fuse for the MFS is under the passenger side lower kick panel..it gets corroded due to moisture and the MFS will not get a reliable 12V)

Be sure the PRN321 indicator is showing the exact gear when you move the shift lever..if it is not..then the shift cable may need adjusting..when you move the lever to 1st gear..it should display 1st gear.

I don't recall..but I think you can pull the error codes for a 1992..do that if you can prior to buying a new gearbox. Get a Bentley too.

Runehang

Thanks again for great tips! I Will check the mfs and its fuse. Just been out trying the car now and tested it with VCDC. A foult appearing is brake light switch. I dont know if that has something to do with this?
I also discover it fail to go in 4. Gear. It look like it is when it should do that the PRN321 lighten up. Foult " gear monitoring signals outside spesification" turns up.
My be the trans is fried but i must check all other options first.
Once again thanks for all help!

Rusty Spokes

The brake light fault is always shown with the VCDC..dont know why but if you touch the brakes it will show if the switch is working after you clear the code. That code is always there.

Check the plug connector for the MFS under the car..be sure it is clean and snaps firmly into position. The "gear monitoring signals outside specification" could be poor MFS voltage, a MFS connection, MFS is out of adjustment or is defective. Dig through the checks for the transmission speed sensor too.

Runehang

I will have a look at this tomorrow and if the MFS is broken in some way, the transmission can behave like i descibed?

Runehang

I have come to the decision to replace my trans whith a second hand one with the same code. Do I need to change the TCM to?

Rusty Spokes

Same transmission code should be fine.

Prior to the effort though..did you say the PRND321 display was showing the exact gear position when you shifted? It is important.

There are 3 fuses on the passenger side..behind the floor board. Inside you will see those fuses and a couple of control boxes..one for the engine (ECU) and one for the transmission (TCU)

The 5amp fuse in there is power for the multi-function switch on the transmission. If it gets corroded..there will be enough of a voltage drop the MFS will not give a good signal to the TCU..and the transmission will not shift correctly.

That area behind the passenger floor board can get wet..the ECU and fuses are vulnerable to corrosion. All kind of weird problems can happen.

Here is a picture..not exactly your model..but is shows the location of the fuses.

Runehang

Thank you again! Yes i am quite sure that it show the right gear.
I have been digging in the passangers footwell and i have been out with the tcu and cleaned it. There are 5 fuses made og steel there. All in different colours. I have cleaned them an Ohm them. But i wonder if there can be fuses behind the driver side footwell that controll the tcu as well?