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grasshopper

Rav4 3 Accelerator Pedal / Revving When Changing Gear

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I know I've asked the question before but I need to be sure this is not a sticking accelerator pedeal. Why is it the RAV4 3 accelerates when you push the car to say 4-5k revs and then change up quickly, but if I pause for 1 second between changing gears it doesnt rev? It makes me look like a learner driver - never had a car before that revs when changing up.

Let's face it the 2.0 VVTI engine is no racer in the Rav4 3, let alone having to wait a second to change gears to make the transition smooth....

One thing I did notice this morning is that there is a noise coming from the engien bay when I press the accelerator pedal - (engine was off when I tried it) - could this be related to a problem I might have?

Any ideas if this is a problem or is it a design feature !?!?!? If it's design, can you get the ECU remapped to stop it happening as it's doing my head in.

Thanks!

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Petrol engines are quite capable of rough gear changes if the engine drops freely back to idle when changing gear. If the driver engages the clutch before the revs are applied, the car will lurch due to engine braking. This was recognised in the eighties when manufacturers had got to grips with carburettors and auto chokes - they could now spend more time on refinement. Toyota were the first to fit dampers on carburettors. In order to return to the idle stop, the throttle linkage had to overcome a little damper - similar to those things you get on modern cupboard doors. This held the revs up long enough for the gear change to take place.

With the advent of fuel injection, throttle damping is done electronically. It sounds a shambles but it does indeed provide a much smoother gear change. Try this; accelerate to about 15mph in first gear and take your foot off the accelerator. At one time it would have thrown you through the windscreen but you will find it just slows down fairly smoothly. This doesn't happen so much with diesels as they have much bigger flywheels and therefor are self dampened.

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Thanks Don - OK so I'm blinded with science! Cant say I'm impressed about this design but guess I'll have to live with it. Think they also missed a trick by not having a 6th gear for cruising - the engine is so raspy at over 70mph, but I guess that's down to the age old engine design...

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Yeah, they did rev a bit with the 5 speed box. They were as good as anything else in their day.

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