Is there such a thing?

I have a 92 RS 3.1 AT. About as bone stock as one can get. 150K miles. Runs like a champ. I come to a stop though, and she dies. Fires right back up. Its has if it doesn't downshift.

What's the deal and is it an easy fix?

Thanks- Matt

 

Converter lockup is controlled by the ECM. There's also a switch on the brake to unlock the TCC when the brakes are applied.

 

Is this switch inclusive with the brake light switch or are we talking about two different switches here? Is this something I can pick up at the local parts store?

Thanks for the info!

Matt

 

I can't remember offhand, I could look it up, or you can just have a look under your dash.

I wouldn't think that your TCC is causing your problem though. Try unplugging the electrical connector for the TCC at the transmission and go for a test drive. If the problem persists, it's not the TCC.

 

More than willing to take other suggestions. The only reason I am leaning on the TCC is that this was an issue on the little Fieros. Yeah, different car, different set up...but same symptons.

Thanks for your help so far.

Matt

 

I'm also having Convertor lock-up issues, is this switch on/near the brake pedal? I posted in the tranny tech section for help but to no avail. Help me please!

 

It's on the brake pedal bracket up under the dash.

 

I hear you are the "ECM/Tranny God".....Thanks for responding, not to hi jack this thread(sorry). So I'm hoping this switch is having the reverse affect on my car.....I'll see tomorrow if its stuck or something. I'm hoping it is stuck in the engaged(un lock) position !!!

 

ECM/Tranny God? Not me, I've never owned my own thirdgen with an ECM.

The switch interrupts the +12v supply to the solenoid. If you can lock the TCC up by grounding the ALDL pin with a paperclip, then the switch isn't your problem.

 

So you read my thread, (and now my hopes are dashed) She locks up through the ALDL with a jumper wire. Any other suggestions
would be helpful.

 

There are 1 or more pressure switches that are wired into the lock up solenoid harness. perhaps 1 or more of these switches are bad. Most units have 1 or 2 in them. Some have more. I always seem to find 1 switch that is bad during an overhaul.

 

In the normal wiring for an F-body the only pressure switch that might give trouble would be the 4-3 pulse switch, but if it was bad it should keep it from locking with the ALDL jumper as well.

 

I'm open to any suggestions. Aside from the brake pedal switch, where might the other one be? The Car in question is an 87 TA....(TPI)....The harness is a donor from another 87 tpi car , FYI. Thanks for any help(a pic would really be nice?).

 

The switches Floor guy is talking about are screwed into the transmission valvebody. You have to take the pan off to get at them.

 

If thats the case then they are not my problem. When I did my swap, the tranny I had used was slipping. So out it came and I put in another (rebuilt one) I had in the shop along with a new(rebuilt) convertor. Tranny number 2 has the same exact problem as tranny number one. I then used the jumper wire in the ALDL to check the torque convertor. The wire locks it up no problem. I wish I would have tried that first before I did the tranny swap and junked tranny #1 !!!!!! Oh well, Live and learn. I would love to track down this problem but on the other hand if I could run it with a toggle switch without hurting the tranny I would do that. What do you think on that matter? Is constant lockup good or real bad? And where would I wire the switch up to?

 

So are there any other suggestions on my issue?

When the car gets warmed up, I come to a stop and the car dies. It basically is not downshifting on its own.

Anything other than the TCC that could cause this?

 

vincode8: Your problem sounds more like the ECM isn't commanding the TCC to lock up.

OilAnalyst: Have you tried unplugging the TCC connector to see if the problem goes away?

 

Apeiron, thanks for your help. I will try another ECM. Is my car 87 specific or can I use other year ECM's...?????

 

It doesn't mean that the ECM is the problem. The ECM makes a decision to lock or unlock the TCC based on various sensor inputs. It could just be choosing to keep the TCC unlocked because of bad sensor data. More diagnosis is required.

 

I have a question about the lockup on the 165 ecm. Pin A7 is the TCC lockup control, with key on and not running you have 12 volts on this wire. As you drive down the road the way it appears to control the lockup is by removing the power to pin (wire) A7. You hit 45 mph and 12 volts is removed.
So I am trying to wire up my lockup convertor to the ecm, as it stands now all I need to lock it up is add power, (I am currently using a manual switch to lock it up) so you see my problem? It's working backwards for me.
I wired in a relay to the A7 wire but it appears that there is not enough amps to pull the relay closed. Any suggestions?

 

Sounds normal. With the TCC unlocked there's +12v WRT ground on the pin through an internal pull-up resistor. When the ECM locks the TCC it grounds the pin, so you'll read 0v WRT ground.

If you want to use a relay, you'll need to wire the relay between +12v and the pin, not between the pin and ground.