How to eliminate (or reduce) ignition retard on A34x auto trannys?

[mamba]

I recently fitted an A342LE auto to my 1JZ Cressida. I would love to know more about this box too btw, I've never heard of a 342 variant before.This box was also fitted with a stage 1 shift kit.
My problem is, I was expecting quick, hard shifts between gears. But at WOT 1st would go to around 4Kish then I can audibly hear the engine retard before it goes into 2nd. The shift into 2nd is a good firm shift but that delay or retard is confusing me. I've adjusted my kickdown cable to full tight but still, there's a delay before changing gears.
Is this due to the ECU or the gbox? I thought a stage 1 shift kit would make changes between gears quick aswell as hard. I know the ECU retards timing to minimise 'shift shock' but I thought a shift kit with high line pressure should make shifts quick and virtually eliminate this shift delay?
Downshifts are good and hard btw.
Could it be speed sensor related? I get an O/D flashing light with code 67. Could it be that my speed sensor(s) could be confusing the shifts on the box?

Any advice greatly appreciated!

[PlacentaJuan]

if you have a kickdown cable then it sounds like the box is the problem

i had a 1jz mx73 that did the farting thing, but once we got a shiftkit installed it went away and shifted perfectly.

how is your trans fluid? if its burned (dark colour) or low then i would give it a change or top up, expecially if you had no transmission cooler before you got the shift kit installed.

[mamba]

The box is a rebuild one with shift kit, trans cooler, new everything and nice red coloured dextron in it.
It can't be the box...right? Could the speed sensors or ECU maybe control the shift speed as well?
I can't hear a farting sound as such, more like it slipping between gear shifts then bang, it engages the next gear. I'm trying to get rid of that delay, slip, timing retard, whatever you like to call it. It doesn't slip gears it only sounds like it when changing gears, that delay, engine revs increasing when not in a gear and at WOT. It's in the transition, the slipping of something I don't know.

[mamba]

Maybe I need stage 1.5 or 2. Don't know. I just want a quick engage not to concerned about how hard it is.

[PsyCo]

I know what exactly what you are talking about and nearly every factory ecu 1JZ Auto I've ever heard going full tilt in 1st gear does it. I'd say it's ecu related not you box.

[Z2TT]

Hi,

Does your car have the POWER/ECON buttons, playing around with those alters shift point settings

[mamba]

I doubt that if you'd floor it, the power button is going to change the shift points. Also, it's not where it shifts though, its the speed at which it shifts.
Must be the ECU then.
Is there a way to run the box without the ECU, purely just on mechanical means?

[brett_celicacoupe]

the auto wont shift without the ecu control.

can you reduce throttle (from 100%) to a point where you are still accelerating full noise but there isnt a retarded shift (literally haha)?

the 2jz has such a point which i estimate is about 75% of full throttle where it shifts without farting but still going hard.

if you could clamp the TPS signal to just below this point then you should be able to trick the ecu into thinking it doesnt need to retard timing on gearchange. this could easily be done with a FCD type circuit (like i already made for you).

i dont see any side-effects with doing this and i believe some people used this method on the 2J for the same problem (BMW turbo) comes to mind.

[PsyCo]

the auto wont shift without the ecu control.

can you reduce throttle (from 100%) to a point where you are still accelerating full noise but there isnt a retarded shift (literally haha)?

the 2jz has such a point which i estimate is about 75% of full throttle where it shifts without farting but still going hard.

if you could clamp the TPS signal to just below this point then you should be able to trick the ecu into thinking it doesnt need to retard timing on gearchange. this could easily be done with a FCD type circuit (like i already made for you).

i dont see any side-effects with doing this and i believe some people used this method on the 2J for the same problem (BMW turbo) comes to mind.

Thats a fkn awesome idea
+ rep.
I've got a turbsmart FCD I'm not using (coz I dont wanna shit my factory twins). I might have a play while my cars off the road.

[madmont]

But at WOT 1st would go to around 4Kish then I can audibly hear the engine retard before it goes into 2nd.
Any advice greatly appreciated!

4K seems awful low revs for a WOT change from 1st
code 67 is OD direct clutch speed sensor signal malfunction

[cambelt]

Brett arn,t you talking about the 2J,s false rev limit thing. Ive never seen or heard a 2JZ fart on gear change like a 1JZ.
Dave

[131OWN]

Ok firstly the only way to "eliminate (or reduce) ignition retard" during shifts is by having a shift kit installed that works.

The ECU has no control what so ever over how long it takes the transmission to change gears as the shift solenoids are of a "On / Off" design. The time it takes the shift to occur is controller Hydraulically.

Ignition retard occurs when the ECU see a differences (slip) between the speed sensors when this is detected the ECU pulls timing to reduce torque during the shift.

If the Tranny is changing gears at 4000rpm at WOT your ECU has a Problem

[brett_celicacoupe]

Brett arn,t you talking about the 2J,s false rev limit thing. Ive never seen or heard a 2JZ fart on gear change like a 1JZ.
Dave

mine farts like a hippie!

ive also heard MR1JZ's old aristo fart on gearchange at dubbo.

you should be able to hear it in this ultra dodgey video: http://www.youtube.com/watch?v=rBORcz_eWrk

[cambelt]

Ok thats the fart , I remember asking about it a year or so ago but thinking it wasnt conclusive. My cressida doesnt fart at all so i dont know what ive done different.
I did reseal the auto before it went in.
If change my gears manually its a pretty firm shift with very little slip but if i leave it in Drive 1st to 2nd is a sloppy shift where as 2nd to 3rd good and so on.
Can you get me yr ecu part no Brett.
Dave

[Dieseltrain]

Ive got a stage 1 shift kit and doesnt fart at all, in fact will leave 2 black lines when shifted . weird .