T/C lockup and Power light questions
 

I have a couple of questions for the tranny gurus out there. In my 1992 SVX I know all about the torque converter lockup in fourth gear when the tranny temp reaches 150 degrees celsius. Prior to lockup my tach reads 3100rpm at 80mph. When the TC locks up, engine speed drops to 2750rpm at the same road speed. It has always been that way and I assume from others this is normal.

Now for the question: In my new 1996 SVX I detect no lockup of the TC at all. Tranny shifts perfectly all the time. Even when the car is not fully warmed up the tach reads 2750 at 80mph; the same as the 92 did with the TC locked up. I have driven the 96 at a steady speed, after acceleration, awaiting the drop in revs that signals lockup but it never comes.

However my mileage for the last tank was combined 24.2mpg, so I figure all must be in order. Is there a test procedure to test for TC lockup? This brings me to:

Question two: In the 92 I had the POWER light on the dash, which was used to diagnose current and previous tranny codes by blinking. The 96 has no such power light. What do you do in order to perform these same diagnoses? Is it performed the same way? As usual any help is most welcome. having the 92 and 96 for comparisons is harder than comparing two 96's.

Hmm... I can see/feel the TC lock up when I get on the highway on a cold morning and it just warms up. (50F I think) Most of the time it not noticable.
The "AT Temp" light in the upper left of the instrument cluster is used for the diagnostic function in the cars without a power light. Being a '96 with OBDII, there is a diagnostic port instead of a coin holder. I think Beav posted the code pulling procedure somewhere but it's a pain. I just have the dealer plug in their "select monitor" to see what's up if the AT light flashes on startup. (I had my transfer clutch replaced on warrenty) ;) B.

John,

To answer your "What do I do" question, please note the following:
Bring money to a dealership, bend oever from the waist and let them use OBD II (aka: OBD 2nd, formerly OBDii) on you.

Good luck.

Larry III

I think an obvious response to knowing if the TC is locked up or not is if you're at highway cruising speed and push the gas a little bit the RPM's should rise. If the TC is locked up then the RPM's will stay the same and increase with speed.

I don't feel my TC lock up but I notice the RPM drop.

I always check by taking my foot off the gas. If the TC's locked up, the RPM's won't drop. If it's not, the RPM's drop like a stone.