TD 4.2 automatic gearbox problem

[ramzgate1990]

hi everyone
ive just registered to this website, i think it could come in handy.

my gq patrol has an auto gearbox.
usually on freeway or over about 80km/hr the engine revs drop a little and it takes an extra gear, but recently it stopped doing that.
now the revs stay high and to push 100km/hr on freeway has become impossible without the revs being high and high boost. the engine sounds like its having a hard time at that speed.

ive taken it to a number of transmission places and theyre all telling me that its something to do with the lockup solenoid or the lockup cylinder,?? im not sure what any of these are but im just worried that it might end up being a big job.
i was wondering if anyone has heard of this same problem and would have a solution

only reason i havent left it at an auto transmission place is because im worried that they may tell me all these things that are wrong and end up charging me heaps of money..


if someone coul give some advice i would greatly appreciate it
thanks
ramy

[Bigrig]

G'day mate and welcome aboard - great people, information and laughs to be found on here, so join in to make the most of it!!!

Yep, it's a lockup issue on the torque converter ... having the same problem on mine right now. Could be the lockup solenoid, the temp sensor in the valve body, the TPS, or another gremlin causing it, so not sure that anyone can tell you what it is without some investigation. It's definitely an auto specialist job though mate, but more than likely not an 'overly' expensive one depending on what's causing it ...

Where are you based?? There's a few different places that members could recommend depending on your location.

I'd be going its either the temp sensor or the TPS as thats where I've gotten to (replaced my TPS and didn't resolve though - grrrr) but Taslucas had the same issue I believe and replaced the temp sensor to resolve (can you confirm Lucas? Thanks boss). That's my next path, and from what I understand, the part isn't that expensive, just the labour to remove the valve body and replace.

Enjoy!!

[Airstrike]

Convert to manual.. just a thought.

[taslucas]

Hi mate. Yep I've had a similar problem. My lock up was engaging and disengaging rapidly on the hwy. While yours sounds to be not engaging at all. I replaced the TPS, torque converter, fitted an aftermarket valvebody. Last thing I did was replace the temp sensor and it was fixed bit only for a month. I only used a second hand temp sensor so I'm hoping that by replacing with a new one it will be fixed. I'm currently waiting for the new temp sensor to arrive.
Theres a bit of info regarding this around the forum. Also you could look st my thread in members rides "tasLucas's tb42 ti"

Ps. Keep the auto, they are WAY BETTER FOR 4WDING.

tappn it

[nissannewby]

What do you guys mean by TPS (throttle position sensor?) Do the diesels have these or are they set up a differeny way? It definitely sounds like a lock up issue as others have stated is normally a trans pro job as it can require certain tooling.

[the evil twin]

Well, the following depends on how much fault finding you want to do but...

Access the Tranny ECU behind the passenger kick panel.
Locate pin 22 and strip a bit of insulation back then using either a multi-meter or an LED or test lamp take the vehicle for a drive.
The solenoid power should appear on pin 22 (above 85 kph etc etc) if it doesn't then it is an input IE, Temp, TPS, Speed etc
If the power is there above 80ish KPH then it is a transmission issue IE lock up solenoid or whatever

You can also measure the continuity of the solenoid to see if it is burnt out but I can't remember what it is supposed to be, sorry.

[Killametre]

If you want any second hand parts I have the lot out of mine which i converted to manual

[ramzgate1990]

Hey Guys sorry I've been a little busy and haven't had a chance to check up on the replys..


Thanks heaps for all that info I really appreciate it
I had the lock up solenoid changed last week at an auto transmission place in Fairfield
Which was closest to me.. I live in parramatta nsw for those who asked... But that didnt fix the problem but he noticed that my temp gauge was sitting on cold for long periods and not moving so he assumed that the temperature sensor was buggered and not allowing the computer to read that the engines warm
Enough to engage lock up.. I think that's what one of you guys said in a post???
So I changed that and got back my regular temperature reading.. Which is always hot as we all know haha but... No it didnt fix my problem!

So anyways I think I'll go ahead n try some testing as u all said and go from there..

Thanks heaps guys again and hope you all had a great Easter!!
All the best


Ramy

[bar1135]

Good luck with this. Let us know how you make out

[ripper]

You can also measure the continuity of the solenoid to see if it is burnt out but I can't remember what it is supposed to be, sorry.

I can probably find this spec if you want to test it. Recently solved a very frustrating problem with ours (randomly losing 1st and 4th gear), and I learnt how to use the AT section of the Nissan workshop manual fairly well.

Well, the following depends on how much fault finding you want to do but...

Access the Tranny ECU behind the passenger kick panel.
Locate pin 22 and strip a bit of insulation back then using either a multi-meter or an LED or test lamp take the vehicle for a drive.
The solenoid power should appear on pin 22 (above 85 kph etc etc) if it doesn't then it is an input IE, Temp, TPS, Speed etc
If the power is there above 80ish KPH then it is a transmission issue IE lock up solenoid or whatever

This would work well in narrowing down what needs testing, as would a manual lock up system.
Ours wont stay locked in with the TCU computer, but when I hit the switch myself it works every time.