hey guys, i've got an auto N/A, and have noticed that when it slips into fourth gear, when you're doin over 70 or so and the box is warm, it kind of goes from 3rd, then halfway to fourth for a split second, then goes into fourth gear. It's almost like its got 5 gears, but i know it hasn't. anyway, my prob is that when it goes halfway between third and fourth, mine sometimes gets stuck and gets locked in. i can floor it as much as i want, but it will stay in this gear and won't drop back to third or second. the power button can be either on or off, it doesn't seem to matter, it still gets locked in and won't change into any other gear. i have to literally stop the car so it automatically selects first, then hope it goes properly into fourth after i reach the desired speed. when i slow down for a corner below 40km/h, it will go into second but then gets locked back in. it's been slowly getting worse, so i was just wondering wat it is. i've also noticed that it does it on cold mornings, when the box hasn't even warmed up, so it shouldn't even be trying to go into fourth anyway till the box reaches 45 degrees. it's pissin me off, coz when i go up hills i have to drop it manually back into second and can't go into third, and i've got no power at all when it does this. any thoughts would be great Cheers

I think you will find it is the lock up Converter.

i think you'll find youve got no tranny oil! top it up and see how you go. theres also a thing conected to the accelerator which kicks the car back a gear when you put your foot down. might be that too.

unplug the lockup torque convertor wire connector.. see if the problem goes away.. if it doesnt, then its obviously not the converter.. maybe check the tranny fluid (as in take the pan of the bottom and imspect it after u've drained it all out and refilled with new ****. I have a funny feeling that the reason ur car wont change gear once its in a gear will be cause u are low or have no oil in there. Chek the tranny cooler lines that go into the radiator end tank.. maybe they been split for a while and u've lost a load of g/box oil ?

mine does that too.. the '5th' gear is the lockup clutch being worn, like exchaser said. unplug the solenoid. as for the no kickdown, etc.. mine has been doing that even after a trans change - its definately not related to fluid. im still investigating mine but basically for some reason its like the electronics shut off and do nothing but the PWR light. unplug the trans computer and drive around and you will see its the same as when it stuffs up. i think its a wiring thing - i changed both trans and computer and its still doing it...

Quote: Originally Posted by natho mine does that too.. the '5th' gear is the lockup clutch being worn, like exchaser said. unplug the solenoid. as for the no kickdown, etc.. mine has been doing that even after a trans change - its definately not related to fluid. im still investigating mine but basically for some reason its like the electronics shut off and do nothing but the PWR light. unplug the trans computer and drive around and you will see its the same as when it stuffs up. i think its a wiring thing - i changed both trans and computer and its still doing it... hey natho, the auto ecu recieves an electronic pulse signal from the speedo in the dashboard, if this signal is no good your auto will not shift properly. I had that problem with mine, just like you said (PWR works but did nothing, like the ecu shuts off). Mine fixed itself after I pulled out the dash board and put it back in. I took it apart and put it back together, this is most likely you problem, you could also borrow a mates dashboard and try that as a test.

thanks mate. the speedo was the next thing i was going to check. i know if the pulse is wrong it causes problems - but remember the auto trans computer only controls kickdown, lockup, and overdrive cancel. i guess its possible that not having a proper speed signal could stuff it up - but i too get the same problem as sweet-na where sometimes when the box is cold it goes into 4th before its warmed up. i'll investigate further soon - too busy at the moment. maybe this weekend i'll look into it some more. Quote: Originally Posted by turboluke Quote: Originally Posted by natho mine does that too.. the '5th' gear is the lockup clutch being worn, like exchaser said. unplug the solenoid. as for the no kickdown, etc.. mine has been doing that even after a trans change - its definately not related to fluid. im still investigating mine but basically for some reason its like the electronics shut off and do nothing but the PWR light. unplug the trans computer and drive around and you will see its the same as when it stuffs up. i think its a wiring thing - i changed both trans and computer and its still doing it... hey natho, the auto ecu recieves an electronic pulse signal from the speedo in the dashboard, if this signal is no good your auto will not shift properly. I had that problem with mine, just like you said (PWR works but did nothing, like the ecu shuts off). Mine fixed itself after I pulled out the dash board and put it back in. I took it apart and put it back together, this is most likely you problem, you could also borrow a mates dashboard and try that as a test.

hey gees thanx guys for all the replies, but i have no idea where to start lookin or unpluggin stuff. my mechanic told me it could be a faulty solenoid, and if so, what price am i lookin at. i don't think its fluid related coz i've topped up my fluid the other day and it says it's got heaps in there. do u guys find it hard to get an accurate reading when the car is running? i ,mean, does the car have to be really warm or do u do it just after uve started it or wat??? also, when u drain the tranny fluid, does it have a gasket you need to replace, and how many mL goes back in once uve drained it. i've checked mine heaps, and its really red and clear and has no particles or dust in it at all, it looks really good. i gather the lock up converter and solenoid is underneath the car near the trannsmission, and i have been screwin around with my dash tryin to get stuff to work (oil pressure and battery volt readers), so could this be why the tranny is ****in up, as someone mentioned the signal from the speedo affecting gear changes. if so, what can i do to try to fix it if it is this problem? thanx a bunch guys, this really is an awesome site, but i'm not that great with transmissions and need a little help. sorry if it pisses u off cheers

*bump* Some original photos have not been recovered yet.

im about to have a play around with mine to try to figure out the no kickdown thing. its not a faulty solenoid, the problem is that for some reason the computer wont even trigger the solenoid (i jacked the back of the car up and ran it "driving" with a multimeter on the solenoids).. i'll check out the speedo thing. as for draining the fluid, what you do is take the sump off let it drain out and put a new sump gasket and filter on ($18 gets u a repco kit with both). takes 2-3L to top it up after a service. 7L if the trans has been fully drained (pulled off the car etc). check the level idling when cold, should be around 1/2 way up the dipstick between L and H.

Natho, I have this exact same problem with my R31. It won't kick down until the trans is hot. I also have a problem with the speedo, it doesn't start working until the engine/trans is partly up to tepmerature. Davehoos in the old R31 Skyline forums pointed out that the speedo curcuit and speed sensor circuit for the trans computer are the same and that they split behind the dash. I strongly suspect that the signal is somehow non existent/lost when cold, because as soon as the speedo starts working, the trans is back to normal. What I am planning to do is put a vacuum switch in the power wire to the lock up convertor, so it will disconnect under load. I plan to either use an adjustable switch, or just try a few to get it where I want it. As for the problems when cold...I just shift manually when I need to.... Regards, Andrew.

Typhoon with my car its fine in the cold - in fact the only time its lost kickdown and always used 4th has been in the afternoon/evenings. dont ask me why!!! just played around today with my brothers VL - i can re-create the problem exactly by unplugging the speedo. no kickdown, always in 4th regardless of the PWR switch. it seems the speed signal is critical to the auto trans computers operation and without it it completely ignores the temperature sensor and does nothing. as i said before i put a multimeter on mine when it was like this and it doesnt even attempt to trigger the solenoids. i'll try my spare speedo sometime in the next few days and let you all know how i go - but i think ive got it. as for the lockup clutch Typhoon just disconnect it, its a pain and i think useless anyway. both our VL's here dont have them connected as they are worn and dont work properly anyway...

hey natho I was just about to tell what you just said (the auto ecu will not function at all without this signal) but you beat me to it good work -> hope it fixes your prob.

Quote: Originally Posted by turboluke hey natho I was just about to tell what you just said (the auto ecu will not function at all without this signal) but you beat me to it good work -> hope it fixes your prob. thanks dude.. i would have posted about it but i prefer to do as much as i can before i bother other people with it.. ive been meaning to look into this for.. hmm... about 2 years now :P it used to happen once every few weeks and now its every afternoon so that got me moving! thanks tho Some original photos have not been recovered yet.

Yeah...but I want the lockup for freeway work...do a fair bit of that, and the fuel economy will help. I just want to set it up so when any sort of load comes onto the engine the convertor disengages. I tow a boat, and it would be nice if it did it automatically. Don't wan't to use a dash switch because it's too easily forgotten! Regards, Andrew.

With the speed sensor in the dash, i've owned 2 vl's, a na auto and a turbo calais manual. in the calais cruise didn't work, and ofcorse the shift in the auto was stuffed up!! (kept dropping in and out of overdrive) The problem with both was the pin for the speed sensor sig to the connector on the back of the dash had a dryjoint. U need to remove the dash and pull it to bits, get the brown circuit board out, and resolder the pin (1of the corner 1s). It's not difficult and i haven't had any problems since. It's probably a good idea to go over all the pins with a soldering iron.

Quote: Originally Posted by Typhoon Yeah...but I want the lockup for freeway work...do a fair bit of that, and the fuel economy will help. I just want to set it up so when any sort of load comes onto the engine the convertor disengages. I tow a boat, and it would be nice if it did it automatically. Don't wan't to use a dash switch because it's too easily forgotten! Regards, Andrew. i used to have a switch on my old calais to disable torque convertor and you right I always forgot about it, if you doing any towing though i'd leave your car in PWR mode, 4th gear is also very weak and wont cop abuse for too long, 4th is usually the first gear to go AWOL

whats the deal with 2nd gear mine slips off its nuts..... how do u fix that?

just thought . vl bti have problems with the wires going to the extra speedo in the glove box area.it acts as an intenna. and can kick down at any time. there is a rework for this but ive heard of non bti doing it.cop cars did it with the uhf/mobile.with micro wavelinks etc these are problem. unlike the r31 the vl has a cable speedo.the pick up and the divideby circuits are not good on vl-vp. the latter ones get power from reverse lights i forget how the vl works. there is more pulses at the speedo than the ecu needs 2 per cable rotation. you dont get kick down bellow 20km/hr???? so no speedo no kickdown. very rare but a turbo has no lockup and some na vl had turbo boxes.with the lock up installed it would try to drive like a manual car.also the lockup wont work on most untill you get 4th.but with hole drilled in the wrong spot it will aplly any time electrically.

hey guys, just got the tranny serviced the other day and my mechanic thought he had found the problem. He said the O rings in the solenoid were all crusty and stuffed, so he replaced them along with fresh tranny oil (which was fine anyway) and new filters and stuff. He tested the solenoid too, although he said it was fine and operating perfectly. set me back $130 bucks, which isn't too bad. i thought he'd fixed it too, but 10kms down the road it started screwin up again. he now seems to think that the lock up converter could be stuffed, and reckons its round $500 on its own, not including the labour to put it in. i read back at the start of the thread where someone, i think natho, suggested to unplug the lock up converter. what would this do my doing this? would i still have a fourth gear, and how hard is it too unplug? can it do any damage to the transmission? i really don't wanna fork out another $500 on top of what my car already owes me, so what else can i do? i might check wiring and simple stuff. natho, you said you could recreate the problem by unplugging the speedo (and i think u have the same problem as me), so could the signal coming from my speedo be too weak? like yours,my tranny seems to work fine on cold mornings/days, but on normal/hot days, it consistently screws up. i'd be interested in knowing what effects would be on the tranny if i unplugged the converter, coz i saw a couple of instances where this was done, so it can't be too bad. sorry bout the length, just have to fix this damn problem!!!! cheers Brad