Auto Shifting problems after GTE A/T swap - solution..ABS? AEM ECU? M/T?

[Pedroby]

Dear all,

I need urgent help with my long running problem with the Supra.

I have swapped out the GE stock engine and replaced for a Supra GTE engine, Supra GTE Auto box incl driveline and Supra GTE autobox engine loom.

 

BUT: the car is not shifting gear how it should. When I drive the car from standing position in the D-gear position. It runs, but not how it should. Full throttle makes it rev a lot, but dont drive fast. Only half throttle seems to work. Kickdown is working, but makes the car slowing down and not move too much.

When I start in L-position I can drive faster and then switch gear to 2-position and then to D-position. So it seems like it's on MANU-mode. But no matter how many times I press the MANU button...nothing happens!!

 

I am getting desperate for a solution and would love to drive the car with it's potential it has. It's a stck J-spec engine with fresh turbos and a full decat with Blitz Nur Spec R at the end and a restrictor ring. The HKS FCD and uprated fuel pump are in the box waiting for installation. But I dont want to take any risks by changing things from stock to avoid more/new problems.

 

My car is a NON ABS example and it seems like the GTE AUTO ECU need input signals from the ABS (wheel speed)sensors. Correct me if I'm wrong as this seems crucial!!

 

I am considering an AEM V1 system which is up for sale in the sale section. BUT, will this AEM ECU also need the input signals from the stock ABS system? Or is this fully programmable? For example, can I/tuning company write a custom programm for me to meet my requirements to drive the car proper without shifting problems?

 

Many thanks in advance for expertise and advises!

[jumpbike]

After reviewing the wiring for mine it does sounds like it could be in MANU mode, I've read elsewhere that other people have had problems with a GTE swap as the GE loom behind the dash routes the MANU wire slightly different and it sounds like yours is permanently at ground. At the back of the ECU the wire going to the MANU button is green with a yellow trace, worst case and saving you replacing the whole dash loom, find the green-yellow wire where it goes into the plug for the wires from the car and check if the wire coming out of the other side of the plug is the same colour or what ever, the MANU wire will be in the plug somewhere it's probably just in the wrong place. Also the wire for the MANU light on the dash might be wrong, the wire colour for this is white with a blue trace, IN FACT... there is a chance that on the GE plug, these 2 are just the other way round which would mean your MANU signal is always at ground through the MANU dash light so stuck in MANU mode, just check you don't have a green-yellow wire going to a white-blue one... and if you do, swap them! or at least make it so the green-yellow one doesn't connect to anything and then drive it

[Pedroby]

Thanks for the good tip!! I will check this out hopefully when it's still light outside once I come home!

Sounds like you might be right!

 

But another problem is that the overdrive is not working. Might this also have to do with the interior loom different wire routing compare to the GTE loom? Something happens when I press the O/D button, but it's freaking and not working how it should.

[jumpbike]

Hey I cant PM people apparently... there are no speed signals from the abs or anything going to the main ECU, theres 1 wire that's yellow-red goes from the abs ecu to the main 1 and the rest all come from the traction ecu, there are quite a few wires go between the traction ecu and the abs one though, mainly because of the wheel speed sensors though for the traction but I've heard you should be able to unplug the traction ecu and everything still work fine so that cant be it, id check those wires I said at first, you do sound like you are grounding the manu button signal and also according to the transmission manual the O/D wont work in MANU mode so there ya go... unclip that MANU wire and give it a bash,

[LOGIE]

Thanks for this jumpbike, ive recently done an NA-TT using all the correct parts loom etc but I dont have MANU function either but I will be looking into those same wires you mentioned. If all else fails im taking my car to Nodland

[jumpbike]

the MANU button just pulses the wire I said to ground when pressed so even if you just have the wire loose behind the dash you can just short it to some bare metal somewhere and see if it changes anything and short it again to swap it back, remember the light wires might need sorting too

[Guest Roger NE]

As per another thread on here, you need to make sure the different speed sensor signals on the Auto Transmission are getting to the ECU OK, or it won't change gear !

[Pedroby]

And is there a difference in the interior wiring loom from the GE car and the GTE engine wiring loom which causes this problem then?

I havent been able to check the wires today! But will give it a shot tomorrow.

I ll check the ECU wires the colours mentioned above and then try the wires at the gearbox that goes to the manu button.

 

Roger thanks as well for your input! Sounds like I am on the rit track to find a solution for my long term problem. Possible solution sounds very logical!

Edited January 22, 2014 by Pedroby (see edit history)

[Guest Roger NE]

Not sure about the GE/GTE loom differences, there are a lot more differences between Auto and Manual.

 

But read the other current thread on here about Autobox Speed Sensors (to save repeating it all)

[jumpbike]

Pedroby - the wires I mentioned to get your MANU working are the only wires from the MANU button, the ecu controls the shifting so there are no wires that also go to the gearbox, everything meets at the ecu

 

- - - Updated - - -

 

Pedroby - the wires I mentioned to get your MANU working are the only wires from the MANU button, the ecu controls the shifting so there are no wires that also go to the gearbox, everything meets at the ecu