Transmission (TC) problem
 

My son has a problem with his 92 SVX. With the Torque convertor lockedup all appears fine. When accelerating lightly the car starts to buck. If you accelerate a little more the transmission will unlock the torque convertor and all is fine. The transmission move very smoothly through the gears and the torque converter enages smoothly Any thoughs? Could this be a TPS sensor problem.

Another question.
How long should it take for transmission to warm up to allow the TC to lockup. My 96 will lockup if the engine is up to operating temp (basicaly by the time I hit the highway). My sons 92 take about 15 km of driving at highway speeds for it to lockup.

how are all the mounts? how's the steering?

A bit more infomation about the car would help narrow down the choices.
How many kls?
Does it have an ATF filter under the battery?

It could be low line pressure, from a blocked pick-up screen in the trans. Or it may have shed the torque converter, lock-up plate, linings.

Harvey. ;)

more info
 

The car has 150,000 KM. The transmission is original. This was a one owner car that appears to have been very well maintained. The car came with all the service records since new, including the bill of sale. Anything that appear wrong with it was repaired. It had a recent transmission flush (guessing less than 10,000 km ago). As far as the filter goes I'm not sure. I will try and get hold of my son and have him check.

The car has started to surge a little when stopped at a light.

All else with the car is in great shape.

Transmission Filter
 

It would appear it does not have an external transmission filter.

The bucking,and the surging that you say it does, could be engine related, or it is the torque converter lock-up clutch. Not much help.

As you may have read, some of the early models had faulty linings on the clutches, primarily the lock-up clutch that seem to shed the linings in flakey bits, that lodged in the cooler to block the ATF flow, and blocked the oil pick-up screen in the trans pan.

The surging, if related to the trans, could be from low line pressure at idle, releasing the forward clutch, caused be the blocked screen in the pan. Or it could be from pieces of lining, picking up and jaming the lock up clutch to cause it to drive through the converter.

It would be best to check the ATF cooler lines to see if there is any debri in there, that would have come from the clutch. Also I would drop the trans pan to check the screen for blockage.

Harvey. ;)

Thanks Harvey I guess the best plan will be to check the lines to the cooler and drop the pan. We'll see if we can get that done next weekend.

Thanks again.