Auto thumps into 5th only after BAS ECU flash

[winaje]

Hi all. Since doing the ECY flash, the auto seems to slip and then thump if I hold power, but only when changing into 5th gear. Happens at even moderate throttle input, I checked the throttle level with IIDBT and happens at about 40%. Also do not see any codes on the IID. Sometimes there is an "F special programs not available" and it locks in 3rd, then when I check the codes it says incorrect gear selected. I can clear the code on the fly and it works normally again until the next load up. Driving me crazy, especially since it's only after the flash.

There is an auto ECU upgrade that I have not done yet as I don't have a power supply to connect to the car...

Any ideas please?

[~Rich~]

I'd be emailing Pete from BAS for advice. ;)

[winaje]

So after a few emails back and forth with Pete from BAS in which he has been very helpful, I have updated the auto ECU using Fastlane via GAP IID. This made no difference. I asked Pete to add the EGR patch ONLY firmware to my IID, and as soon as I flashed the standard ECU with EGR removal only, the auto is shifting perfectly again...

So no idea what the actual cause is, but I do know that it's only there with the BAS ECU power upgrade. Back to the emails now to see what else can be done.

[justinc]

How many km on the trans?

[winaje]

How many km on the trans?

366k, and don't tell me it's about to die, that'd just about top off my year

[DiscoJeffster]

At 336k I'd be nursing my vehicle to a healthy age, not adding power to finish it off, but that's just me [emoji3]

[justinc]

The incorrect gear selected fault that can be cleared and driven again until next load point usually means there is excessive difference in output shaft to input shaft speeds. The torque converter lockup clutch is usually to blame however overall clutch wear will be added to that, so yes at those km you are most certainly on borrowed time. As soon as you add 20 to 30% more torque line pressure can't clamp the tc lockup hard enough and it starts to slip.

Sorry but it does look that way. And just to make you feel 'better' you have got about 100k more than most.

Jc

[winaje]

The incorrect gear selected fault that can be cleared and driven again until next load point usually means there is excessive difference in output shaft to input shaft speeds. The torque converter lockup clutch is usually to blame however overall clutch wear will be added to that, so yes at those km you are most certainly on borrowed time. As soon as you add 20 to 30% more torque line pressure can't clamp the tc lockup hard enough and it starts to slip.

Sorry but it does look that way. And just to make you feel 'better' you have got about 100k more than most.

Jc

Thanks Justin. Well I've de-torqued, so hopefully I can get another year or so out of it. By that time I can probably afford the $6k or so to replace it. Just so I know, will it go "bang" and lose all drive at once, leaving me stranded, or is it more likely to get slippier and gradually fade?

[justinc]

Would be worth getting an opinion from A&b in Dandenong or Manuel Automatics in Thomastown however we have just had an almost identical issue on one with 100k less. Non remapped too. New trans and its like a new car☺
The problem will become worse slowly and usually won't leave you sttanded but id probably not tow or venture out of town

Jc