Triptronic not shifting in auto

[sl4444]

Hi guys

I have a problem with my transmission and here in the UK the automatic/triptronics are not very common.

So any help will be great, well my transsmisson wont shift in auto correctly it is very irratic and cant decide what gear it wants to be in, when in triptronic 'M' mode it shifts very jumpily and goes from 1st through to 4th but wont shift to 'Overdrive',

Ok so i have changed the atf with genuine toyota t4 and took the sump off and cleaned the 'screen' filter type thing.


So anyone shed any light on this?

Is there a way you can reset the transmission ecu?


Seth

[Dasher17]

First off, you might need to clarify a little.

4th gear IS overdrive in the auto celicas.

Tiptronic is much MUCH slower to respond than normal shifts are, especially in cold weather on startup.

Depending on how you drive an automatic, it can definitely feel like it won't make up it's mind which gear it is in. For example going from cruising in 4th to WOT will feel weird.

[x310gtsx]

4th gear IS overdrive in the auto celicas.

this.

also i find, in tight traffic, that the auto has a hard time choosing which gear to be in, in general. when 2nd gear would be ideal, the auto shifts to 3rd, or when 3rd would be good, it kicks it up to 4th; making getting around a pain sometimes. So i suggest that you use M mode when things get tight to keep the tranny from doing its gas saving thing. Or at least that's what I do, cause i just hate the feeling of floating between gears in 30 mph stop and go traffic. :shrugs:

[sl4444]

Cheers for the replys guys,

The gearbox when in fourth seems to have a small half gear above it? May just be my imagination ;-).

This has all happened since I had my car rolling road tuned, using a piggy back type ecu ( I now have a PFC to go in on Friday) could this be the cause?

When I got the car the tranny was perfect and shifted like silk so I know what it SHOULD feel like, it now just seems unhappy.
When pulling away even in very light throttle it will rev up to the red line and hold it there for ten seconds or so then shift to 3rd then 4th then back to 2nd all whilst trying to go like 10 mph or so?

I drive in m mode most of the time anyhow but the wife likes to drive it in auto.

[GSBoek]

The gearbox when in fourth seems to have a small half gear above it? May just be my imagination ;-).It's not a small half gear, it's the torque convertor locking up in 4th gear.

This has all happened since I had my car rolling road tuned, using a piggy back type ecu ( I now have a PFC to go in on Friday) could this be the cause?I guess you'll have to go back to stock and see if that changes anything, if not then I'd start thinking about the transmission governor.

[Dasher17]

When I got the car the tranny was perfect and shifted like silk so I know what it SHOULD feel like, it now just seems unhappy.
When pulling away even in very light throttle it will rev up to the red line and hold it there for ten seconds or so then shift to 3rd then 4th then back to 2nd all whilst trying to go like 10 mph or so?
Yea that's weird. Sounds like it could be that piggy back ecu you have on there, something must not be right with the tune.

I didn't realize a PFC would even affect an auto that much, if any.

[sl4444]

Cheers GSboek now you mention the torque converter locking up that makes sense lol sorry for the dumb as question lol

Dasher17 as far as I am aware you need to run the PFC along side the standard ecu as that controls the autobox? As I said info in the uk is so limited on these transmissions :(

I am having the PFC fitted and tuned on Friday so fingers crossed that all is well in transmission land again after that.


Seth

[sl4444]

Ok so heres the update,

Really need some help here now, The car works perfectly when cold in auto and triptronic modes but as soon as its got a little bit of heat in it it refuses to change into 4th again and the M mode just flashes and doesnt work at all?

any ideas


seth

[GSBoek]

I'd guess something is up with the coolant temperature reading. Is this with the PFC?

[Dasher17]

Like I said in the other thread, the M mode issue I would ask the shop that tuned your PFC about. It sounds like something wasn't connected properly. Not a lot of cars that age have tiptronic so it might have been somethign they overlooked when reconnecting things.

And like GSBoek said, my guess is you just need to replace the thermostat as it probably is reading wrong.