First thing my overdrive is not working, but I plan to get this fixed next week. In the mean time I've been driving around with the car on the motorways. Today, I found that I can push past what I thought was the accelerator floor... I can smoothly push the accelerator peddle to the point where it stops... The car smoothly accelerates, albeit at high REVS, maxing out at 4500RPM... But then I found that if I push a little harder... The peddle clicks over a "notch", the peddle is now to the floor, and the engine kicks and suddenly rockets up to nearly 6000RPM!! What is this? Is it normal?

 

Thats the mechanical overdrive kicking in. You've got the electronic button on the stick and then the mechanical one connected to the throttle.

 

What is the mechanical overdrive? What is it meant for? It doesn't sound to good for the engine... And should I be pushing past a restive notch? Or it is something that needs fixing to make a smooth peddle push through the entire travel of the peddle?

 

I found an online Volvo Manual which talks about kickdown...

Kick-down
Automatic shift to a lower gear is achieved by depressing the throttle pedal fully and briskly. An up-shift will be achieved when approaching the top speed for a particular gear or by releasing the throttle pedal slightly. Kick-down can be used for maximum acceleration or when passing at highway speeds.

So it looks like the transmission was shifting down a gear, causing the REVS to rocket... and I guess overcoming the "notch" counts as a brisk pedal press...

 

You're in the right frame of mind. That "notch" is supposed to be there. Though they seem to have the same effect, the OD button only turns off the OD (duh right?) but the kick down actually drops out of OD and then down an additional gear for extra power. When you get your OD fixed test it out and then compare it to your newly found "notch." Big difference.

I know that the car/transmission/motor was all designed for this little feature but i get a little nervous using it too. I guess it all depends on how many miles you have on your car, how well it's been maintained, etc. Mine.....lets just say i could have taken better care of my 240. I'm worried it'll revolt if i push the kickdown..lol

 

Well I think the car was as surprised as I was when I found the kickdown, especially while travelling at 100kph. The engine was sputtering afterwards, when accelerating normally, and it sounded rough in the exhaust... It seems to be back to normal now though... phew...

 

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You should probably pull the codes and see if your engine thinks there's something wrong. There's a link on the general page explaining how to do this...pretty easy actually.

 

BMW's also have one of these kickdown switches... in the form of a small button under the accelerator pedal that clicks in when you push the pedal right to the floor. Very fun indeed![8D]