Torque converter won't unlock

[immortality]

at what road speed is the torque converter suppose to unlock?

was cruising along the motorway and slowed down in traffic, gave it a little gas to keep it moving but the TCC didn't unlock. engine was down to 1500rpm and wasn't happy. had to give it a good boot full for the TCC to unlock. it has done this a few times now. one day last week i think the TCC was still locked when i was doing about 60km/h after coming off the motorway.

has also developed a stumble/flatspot of idle.

[python_hunter1]

my convertor locks and unlocks at spot on 100 kmh, with the rpm siting at 1900rpm when it locks. thats with the standard diff ratio.

[hako]

Check the throttle position sensor(TPS)....also the vehicle speed sensor (VSS) - either can make the ECU think the car is still cruising and keep the TCC locked up.
Good Luck

[immortality]

gonna try another TPS today and i hope that does it. although i suspect the VSS is probably the issue

[Thomas1]

My converter will lock in third at around 60km/h and 4th at 80km/h

[immortality]

changed the TPS and also changed it's position slightly. normally i'd put it on and then line up the holes for the screws and do it up. this time i fitted the screws but turned the TPS as far as possible clockwise before locking up the screws.

engine just about stalled when i started it. gave it a stab on the throttle and the idle returned to normal. quick spin and things seem better. throttle response is back. kick-down is quicker etc.

i think there is some loose wiring somewhere. when you go over a large bump the engine dies and comes back to life. engine check light flashes once. i'll check fault codes shortly but i'm not holding my breath on that one. gonna be hard to figure out. where ever the problem is it must be at a important sensor as the engine dies completely for a second

[immortality]

looks like the converter locking problem is still there

i suspect the engine dying issue may be fuel related (in particular the fuel filter). only does it in 1st gear when you nail the throttle, if you nail it in 2nd it will pull right to 5500rpm without missing/surging etc

[hako]

Maybe the TCC solenoid is sticking or the wiring is bad. If you can identify the correct colour wire that powers the TCC solenoid you could cut it and put a manual switch in....I've read of people doing this in the states but have no personal experience myself.