TC Lockup Problems and other issues....

[armybmbsqd]

It has been colder than a tichs wit here lately and yesterday I noticed my TC is not locking up. This morning I checked the tranny fluid and it is a little low. Can this cause lock up issues??

 

I keep the P/C switch in the power mode. If it is in comfort mode the tranny seems to slide into gear instead of shift. I switched the tranny controller and the TPS with some spares I had laying around but still does the same thing. Any suggestions??

 

Thanks

Pat K

89 MJ

4.7 Stroker

[Geonovast]

Drop in a stick :brows:

 

I'm not an auto expert..but I can see how low fluid would cause the converter to not lock up. Top that off and see what it does.

[armybmbsqd]

Topped off the fluid and put the other tranny controller back in and it still will not lock up.

[Geonovast]

Is there some kind of solonoid in the converter itself? Could be that?

[LEAD_NOT_FOLLOW]

As far as the torque convertor lock goes. Solenoid 3 is unique, in that it only controls torque converter lock functions.

 

The TCU is programmed to force torque convertor lockup when engine RPMS's are above a certain point (not sure exactly what RPM though?), and you're at wide open throttle (WOT). Why? easy, top speed. The AW4's torque convertor has a very high stall speed (translates to high torque multiplication factor, and higher RPM off the line).

[FxRacing282]

if that dosent solve it, drain your tranny fluid and then put new stuff in

[Eagle]

One of my NAXJA friends could never figure out why his torque converter wasn't locking up. He finally just wired a toggle switch to the solenoid. He leaves it unlocked around town, and uses the switch to lock it on the highway.

[comancheman]

could someone explain exactly how a torque converter functions? i never really understood them

[Geonovast]

Very, very BASICALLY.

 

Think of an inverted fan pushing hydraulic fluid against a fan inside of it, once it builds up enough pressure from spinning fast enough, it causes the internal fan to rotate, turning the transmission. This is what allows the transmission to shift, since they can be turning at different speeds, and usually are unless it's locked. Also why you can idle without the car moving. There's always a slight amount of pressure being put on, and that's why when you left off the brake in an auto it begins to move forward, while a clutch completely disengages the motor from the trans, and when you left off the brake on a level surface with a stick you don't go anywhere.

 

www.howstuffworks.com has some decent pictures and a more detailed explanation.

[armybmbsqd]

I got the TC issue fixed tonight. Sometimes it's the simplest of fixes that you just can't see.

I did a 96 brake booster/MC swap when I did my stroker install. I had to modify the brake light switch to make it work. Tonight I removed the driver side floor mat to dump out the snow and water and noticed one of the wires was loose. :oops:

At least I found it

 

Pat

89 MJ

4.7 Stroker