Revs Hanging When Changing Gear

[Zim1]

I wonder if anyone has had the same problem (or if it is a problem), when i change gear the revs hang for a while, its maybe only a fraction of a second but is quite frustrating as it makes gear changes take a little longer than normal. It seams the accelerator is not very responsive. Any ideas??? 2000 4.2 2l VVTI manual.

[IanXT4]

If you do a search on this and other forums you will find this is a common question and is a design feature of modern engines with low emissions.

When I first bought my RAV 4.2 petrol it annoyed me, after a couple of weeks your driving adjusts and you don't notice it.

I believe its implemented by the ECU to ensure complete combustion under sudden throttle cutoff.

Ian

[jedi134]

Could it be a faulty clutch mechanism switch? have a look underneath at your clutch pedal? does it have a switch on it, like the brake pedal does?

[IanXT4]

Google Throttle Lag or Revs hanging and you will find hundreds of hits from all manufacturers talking about this issue.

an example is

http://www.fordwiki.co.uk/index.php/Throttle_Hang_Fix

Many forums talk about fixes to get round the emission control and make it more "throttle like" but to be honest after a few weeks you adapt.

"Resistance is futile"

(Also I believe any switch on the clutch is just to kill the cruise, if fitted, and would not affect the throttle control)

[Zim1]

Google Throttle Lag or Revs hanging and you will find hundreds of hits from all manufacturers talking about this issue.

an example is

http://www.fordwiki.co.uk/index.php/Throttle_Hang_Fix

Many forums talk about fixes to get round the emission control and make it more "throttle like" but to be honest after a few weeks you adapt.

"Resistance is futile"

(Also I believe any switch on the clutch is just to kill the cruise, if fitted, and would not affect the throttle control)

Thanks for that guys, i was just hoping that is wasnt a fault, tried to google it before posting but didnt have any luck so hence the question, thanks for the link, i will just adjust the way i drive.

Thanks again

[Mike JD]

If you do a search on this and other forums you will find this is a common question and is a design feature of modern engines with low emissions.

When I first bought my RAV 4.2 petrol it annoyed me, after a couple of weeks your driving adjusts and you don't notice it.

I believe its implemented by the ECU to ensure complete combustion under sudden throttle cutoff.

Ian

Well blow me! Driving a RAV that had been sat still for almost a year, I though about sticking throttle cables, valves and heaven know what else. In the end I too have lived with it and while I don't like it, it isn't the end of the world.

Now all I have to do is to stop it see-saw surging down our drive in the morning in first gear and with a stone cold engine and I can cross off another of its funny habits as normal.

Funny habits? I wear them all the time.

Mike D

[jedi134]

Clutch pedal switch is worth a try too, easy ones 1st

Have a look here

[IanXT4]

Interesting link Jedi134, but I suspect that the VW ECU is using a different sensors/switch setup to the RAV4.

My car 2004 XT4 Petrol 4.2 VVTI is not fitted with cruise control and as far as I can see has no switches on or near the clutch pedal.

It has exhibited this slight momentary throttle hang since new.

Ian

[anchorman]

I would discourage anyone from trying to fix this. It goes back to the days of carburettors when manufacturers were fitting dampers to hold the revs rather than allowing them to drop like a stone. It aids emmissions, smooths out gear changes and improves the refinement. Just try something (petrol or diesel). On a quiet road, accelerate up to about 4000rpm in first gear and then as quickly as possible, take your foot off the accelerator. At one time it would have nearly thrown you through the windscreen but you will find it just eases off smoothly and automatically.

The manufacturer has gone to great lengths to make it hang on to the revs. Don't look for ways to disable it.

[jedi134]

@Anchs: Is this problem just on certain 4.2 motors? As I`m pretty sure my Rav does not do it, well not to any extent that I notice anything strange? Maybe I have adapted to it?

@Ian XT4: Yeah I know its from a totally different car but just thought it might be work a try, Even Vw`s without cruise control still have this switch fitted to the clutch pedal.

[Zim1]

I hear what you are saying Anchorman with regard to taking your foot off after reving. Its not too much of a problem, just wanted to see if anyone else has come accross this..

Thanks all

[anchorman]

@Anchs: Is this problem just on certain 4.2 motors? As I`m pretty sure my Rav does not do it, well not to any extent that I notice anything strange? Maybe I have adapted to it?

Only on petrols, try taking the revs up to about 3000 and dip your foot on the clutch as if you are going to change gear but don't, leave it in gear with your foot on the clutch. You will probably find it hangs on to the revs and then gradually soaks back to idle. Some cars (not RAVs) have a neutral switch so it would hold the revs unless you selected neutral. 4.3s do it more than 4.2s.

It isn't a problem as such it is designed that way.