Howdy !

I've been told that the A4's converter lockup is temp controlled - meaning that before the trans reaches a certain temp, the converter will not lock up .

My car's trick is that when it is cool out - 60 degrees F or lower - the thing gets stubborn and does not always want to smoothly go in , even when the car is past the 1/4 temp mark.

(For reference, my old ' 99 T/A did not wait - at least, not that I remember.)

Different days it has different ways - like it has a mind of it's own.


Is there a tranny mounted temp sensor that controls this, and is perhaps easily replaceable ??

I have a Vigilante 2800 stall - could the lock up solenoid be bad ?

Since it has an aftermarket tranny cooler in series with the factory ( in-radiator unit ) , could it be over cooling ?


Any thoughts/help is appreciated - thanks !!


Britt

Thanks in advance !


Britt

If the fluid is too cool you could have problems locking up. What size cooler are you runnning?

Brian

It's the engine temp that controls the lock up.
Engine temp must be at least 170° before it will lock.
Any high stall converter will make lockup variations much more noticable. It's all part of the game

It was whatever was on the car when I bought it.

I'll have to see if there is a P/N somewhere.


AL SS590 M6 -

thanks for the tidbit !



Why is the engine temp important, though ? I follow the rationale behind the tranny temp , but ??

Thanks !!

Britt

Ahhh.. thats why I am having the same problem.

It's mostly for emissions so that the motor doesn't lug down when cold.
And trans fluid temperature has nothing to do with it. The ECM locks the converter, but only when the motor is warm enough to pull clean at low rpms.