forum.audiv8.com Foren English Audi V8 Forum ZF4hp24A shift problem

The gearbox wont sift to 4th in automatic. If program is switched to manual 4th gear engages normally.

i.e. when cruising 100km/h in manual, switching program to either sport or economy will cause the gearbox sift to 3rd regardles if the gearlever is in D or 3.

No fault codes in ecu or tcu.
Well serviced car with 195tkm genuine mileage.
Right amount and the right quality oil in gearbox, frequently changed.

Other than this the Car performs 100% ok.

I'm out of ideas, help would be appreciated.

hi Antti!

It may help to reset the Gearbox control unit. Just unplug the battery overnight and then try again ...

I've had the battery and tcu unplugged for a hour or so. did not help. Maybe I'll try a longer period..

The odd thing is that once or twice the 4th gear remained engaged when I changed from manual to automatic during highway cruise.

Could the program selector be malfunctioning somehow? The switch has 3 wires plugged in it, how does it actually work? Disconnecting the switch doesn't make any difference.

Hi!

Do you have try to read the error codes from TCU? Perhaps some kind of contact error in the sensors or relays in the box... I mean after you get the battery disconnect.

No error codes in the tcu or ecu whatsoever. I think it's definetly a contact fault.

I have the ZF manual for the geatbox, only if my german was a bit better..

I have an idea that maybe the 4th gear solenoid is actived trough 2 different circuits depending on wheter the probram switch is on M or S/E. Though I haven't confirmed this yet..

Advices are welcome..

Good morning.

What rim are on your V8 show on the picture?
(rim and tire size)

Good Afternoon

The wheels are BBS RS236 11x17 et~0 shod with 255/40R17 rubber all around.

Wow, huge! But nice!