VR V8 auto won't shift properly

[clubbie93]

My 12/93 V8 Clubsport auto has suddenly decided not to shift up properly. It will start off in 1st gear and won't change to second until the engine is doing something like 4,000 rpm and sometimes won't shift up at all. It is also slow to shift up in other gears if I manage to get that far. This has happened quite suddenly and it has been perfect until then.

When I shift from neutral to Drive it gives a solid jerk forward which is not normal - usually quite sweet and smooth.

I have dropped the oil pan off the trans and replaced the fluid filter and a new belly full of Dexron III but the problem is still there. On the very odd occasion it will suddenly decide to go back to normal but then it will play up again.

Has anyone seen this kind of problem before ? It seems to me that the electronic control either inside or outside the trans is getting its signals screwed up.

 

[BlackVXGTS]

Sounds like a classic TPS (Throttle Position Sensor) problem - you need to replace the sensor. Instructions in the attachment below. Make sure you replace the washers, spring and drive adapter correctly as per the diagram.

Also, check to see if you have any error codes set:

http://forums.justcommodores.com.au/threads/checking-error-codes-vr-vs-revised.22307/

 

[clubbie93]

Sounds like a classic TPS (Throttle Position Sensor) problem - you need to replace the sensor. Instructions in the attachment below. Make sure you replace the washers, spring and drive adapter correctly as per the diagram.

Also, check to see if you have any error codes set:

http://forums.justcommodores.com.au/threads/checking-error-codes-vr-vs-revised.22307/

Thank you for the info. I'll try all that and see how I go.

 

[clubbie93]

Sounds like a classic TPS (Throttle Position Sensor) problem - you need to replace the sensor. Instructions in the attachment below. Make sure you replace the washers, spring and drive adapter correctly as per the diagram.

Also, check to see if you have any error codes set:

http://forums.justcommodores.com.au/threads/checking-error-codes-vr-vs-revised.22307/

Hey BlackVXGTS I pulled the throttle body off, disconnected the TPS and the other sensor wiring, cycled the throttle butterfly from fully closed to fully open a few times, put it all back together and the thing now performs like normal. I think this tells me that the TPS should be replaced anyway. I'll proceed on that. Thanks for the help.

 

[Mr sludge]

I had same sort issues my V8 auto, got new TPS suggested by automatic mechanic and bingo. It was slipping high rev change shuddering. TPS fixed problem.