Aristo/2JZGTE Auto dropping out of gears when cold..

[BMWTurbo]

Hi Guys,

Lately I've been having some strange issues with my 2jzgte aristo auto... In the mornings when driving down the road it will take forevere to change into second. I can actually get halfway down toe road before it will change even on very light throttles. It's slowly been getting worse which concerns me a little, but after about 1-2klms down teh road it will work fine as though nothing is wrong.

One thing I have done is put it into second manually and it will hold gear okay, but when you change to drive, it will drop into 3rd, but then start free revving (ie change back down to first) after a little bit.

It's got me stumped and all I can come up with is that the fluid is cold and the solenoid is sticking. But this doesn't make all that much sense seeing as it will hold 2nd if you manually put it into gear...

[MR22ZZ]

have you changed the tranny fluid yet?

[BMWTurbo]

Did that about 2-3months ago when I changed the transmission. Transmission has been worknig fine up until recently.

Only used type IV toyota fluid. Levels appear fine and haven't changed over the period.

[CrUZida]

I had very similar problems when I had neither speed sensor going to the ecu.
The one on the box had not been plugged in, and the one in the dash died.
But I'm pretty sure the CEL and OD OFF light were flashing errors at me.

I ended up driving around for 2 days with the shifter in '2' until I got time to fix it.

[ProjectSleeper]

Sounds like the same thing as mine - Line Presure Solinoid was faulty..

Ordered a new one thru Toyota - should be here in about a week...

[BMWTurbo]

Thanks Guys... Does the pressure solenoid come out with the valve body??? I have a spare G'box with a slipping second that worked okay, maybe I can pilfer from it?

[BMWTurbo]

Mucking around with it this morning. When you manually select second gear, it will change between 1st-2nd and back as though nothing is wrong.

If you change into Drive it will drop in to third but can slip from 3rd-1st with no notice... Once I'm a couple klms down the road, back to perfect working order.

[BMWTurbo]

I'm a little lost atm... I've put an O/D light on the car and it appears to be throwing either code 8 and 9 or code 89... I can't find any reference to any code 89 though?
I was looking at the codes and the sum of thier numbers whioch are all different, sum of 62 is 8 anmd sum 63 is 9 which is S1 and S2, which makes sense...

The ECU is also throwing code 78, which is the fuel pump control circuit. I'm wondering if this could somehow be related.

[BMWTurbo]

Found it..... Error 89, Trac ECU circuit.

http://space.toyotaclub.be/TDP/001_s...%202JZ-GTE.pdf

Page 56

[BMWTurbo]

Turns out it was the selector switch.

Well I can't be certain until tomorrow morning, but I've changed the switch, plug and wiring and the car seems to work fine now.

[cambelt]

maybe yr revlimit prob will go away also.
Dave

[BMWTurbo]

I don't believe so. I've fitted the working/tested original switch from the box that I broke 2nd in.

The supra ECU did not Rev limit with either the old box/switch or a the second box/switch, but the aristo ecu still did with the second box fitted....

[cambelt]

What part no supra ecu did you get , I got one from a 95 jza 80 , same part no from 93 too 96 auto TT.
i want to check the wiring differences between them . I know the supra ecu has a manual button instead of a ect pwr button . ( also momentory switch in the supra ) supra ecu also ouputs to the manual bulb in the dash .
Dave

[BMWTurbo]

What makes you say it's a momentary swtich??? I haven't tested one to be honest though, but according to the diagrams I have it's a latching.

I didn't worry about connecting the 'manual' bulb in the dash. I've also noted the supra ECU will not let you start off in 2nd gear, it always drops back to first no matter what 'mode' you are in.

[cambelt]

I service a auto TT jza 80 and the man button is momentory .
Also can anybody with a 2jz-gte and auto in whatever car tell us how yr auto changes into second gear while yr flat to the boards . They seem a bit slippy at first (the beginning of the change into second ) then a firm change . Certainly not like a 1jz that retard the timing on gear changes .
Dave