The Toyota Landcruiser Owners Club

[Pugwash]

Been having odd torque converter lockup problems and im hoping someone can help

the lockup clutch physically works

BUT i can only get it working in the following conditions:

On a motorway accelerate up to around 70-80 (its not a consistant speed) and the gearbox will lockup and stay locked until i force it to down change by using kickdown or by braking. It unlocks fine. Once it has locked up once it will lock and unlock at around 42mph no problem (bit early probably caused by gearing differences due to bigger tyres) for the rest of the journey.

When i turn the engine off and then restart the car a bit later then lockup USUALLY doesn't happen so i have to get up to 70-80 again

i have a diagnosis in mind, but would like to hear from others first!

[Google]

[wildsmith]

What year or gearbox? If it's the later box, are you allowing for the fact that it won't lockup until the engine coolant temperature reaches normal? I asume the earlier box does something similar but with ATF temperature.
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Jon m0zxj

01 UZJ100 lifted (AHC & 40mm BL), ARB locked f&r, cryo'd 4.88's, TJM front bumper, 12k goldfish, sliders, rack, snorkel, 35's, storage, aux power etc.
93 HDJ80 sold
94 HDJ80 RIP

[Desperatezulu]

Mine also locks up at around 40mph - I have standard tyres and A442 'box, so that sounds normal. Are you suggesting that if you accelerate up to 80 and achieve lock-up, if you then take your foot off the accelerator and let it coast down to 30mph, it remains locked? If so, how do you know this - if you gas it again, it should kick down? I suppose that if it doesn't kick down and the engine "bogs" on re-applying throttle then that would confirm that it's still locked!   But you have indicated that it does kickdown ok...
Not sure I fully get the problem... I wouldn't have much of an idea anyway, assuming you've ruled out ATF issues such as cooked fluid or not properly warmed up.

Cheers,
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Andrew

'98 LC80 4.2TD VX 24v

[joinerman]

My 94 has the A442F box & annoyingly locks up at 38mph, i say annoyingly because when following people in a 40 mph limit who drive just under the limit it's forever locking up then dropping out, mine will also lock up straight away from a cold start.

[wildsmith]

[Pugwash]

well don't know where to start with this

reckon it could be temp related- but where the hell is the sender for the ATF? as if i could change that quickly and cheaply then that would be easier than droppping the valve body (which really really really scares- all those little springs!). Also the valve body has two solenoids that are unmarked C1 and C2- but nowehere does it seem to say which controls TC lockup- which one do i test?

[wildsmith]

You need to tell us what year the vehicle is, or what box is fitted to be able to help.
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Jon m0zxj

01 UZJ100 lifted (AHC & 40mm BL), ARB locked f&r, cryo'd 4.88's, TJM front bumper, 12k goldfish, sliders, rack, snorkel, 35's, storage, aux power etc.
93 HDJ80 sold
94 HDJ80 RIP

[Pugwash]

sorry

it's a 93 UK 1HD-T spec with A442F box (the one with the overdrive button)

had the T/C rebuilt about 8 months ago by the gearbox people in Exeter (can't remember their names but iirc they are ones you recommended Jon) and it definitely works ok- just get this random lockup thing

it could well be a temp sender problem, but i can't find a reference to a G/Box temp sender in either the EPC or FSMs (although i could well have missed them). I also suspect a dodgy solenoid- because once it starts to work it works ok- almost as if the solenoid was sticking. First port of call for me would be the temp sender as long as it is accessible and reasonably easy/cheap to fix/replace!

[Pugwash]

ps i also have far too long kickdown cable so its not quite adjusted right, but i didn't think this affected TC lockup?

[jvoelcker]

Another thing to check is the Throttle Position Sensor - I am coming across more and more 80s where these haven't been set correctly - on the earllier A442 the kickdown cable setting seems to be quite critical, but on the later A442F boxes the TPS setting seems to have a greater effect.

Check the settings on the TPS initially and also check the condition of the oil - most 80s I come across have really shitty oil in them which can make a bit a difference to gear changes, etc.  For some reason once the cars come off dealer servicing the gearboxes seem to get ignored.
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Cheers,

Julian
1994 HDJ80, with loads of mods without looking too obscene
1997 KZJ95 - Gilly's - plain black and muddy on BFG ATs.

[wildsmith]

[jvoelcker]

Jon,

I was actually referring to the TPS on top of the injection pump found on the later auto boxes - I have seen some of these removed and then incorrectly put back on as well as some that have gone out of adjustment.  I have made up a wiring harness to easily test these and find around 50% of them are out of sync.  If you follow the circuit in the manual it is very easy to test.

Also the Exeter firm would have been promoted by Christopher Bell, although obviously Ian isn't a fan  
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Cheers,

Julian
1994 HDJ80, with loads of mods without looking too obscene
1997 KZJ95 - Gilly's - plain black and muddy on BFG ATs.

[Pugwash]

dammit more stuf to check lol

anyone know where i would find the temp sender for the ATF as a place to start?

pretty sure the oil will be ok as it was only changed 8,000 miles ago- it was flushed and fully replaced as the TC was rebuilt!

[Oaktree]

Hi

I've had failure of both TPS and 'Lock-up' solenoid.

My TPS failed because the carbon track (think crackly volume control), had worn out in the middle of its travel so the auto-box ECU wasn't getting the full message. It was like driving a kangaroo! Slow speed Ok (Small throttle opening) , High speed OK (Large throttle opening), Mid-range: No signal = No ECU idea = Kangaroo gearchange.

However your problem does sound like intermittant Lock-up solenoid. From memory mine lasted about 2 weeks before it wouldn't lock at all. To get at it you need to take the sump off the auto-box, then the filter screen, then I think the solenoids are accessable. There are 4 solenoids, 3 different versions (different brackets) and unfortunately (because I cant remember which one, although mine looked very burnt)  the version of which there is 2 off, one is for lock-up. The part No. is T85420-60060 (about £100 in 2004!) Watch out for ATF dripping into eyes, ears etc!

Hope this helps.
Good luck
Nigel

93 VX 1HD-T A442F Auto

[wildsmith]