Acceleration problems

[Jane Doe]

Hi all, my wife owns an 07 1.6 auris and I had the pleasure of taking it out today. I noticed that when you press the accelerator maybe half way and hold it, the revs climb steadily then shoot up and fall again quickly. For example I was on a carriageway in 5th and put my foot down to overtake. The revs shot up from just under 4k to 5k and then dropped straight down to 3.5 without my foot moving. Seems like it just lost power. It seems to happen in all gears under heavier acceleration. Could there be something wrong with the vvti? Thank you in advance for any replies. 

[alan333]

Could be your clutch on the way out.  Try pulling away in 5th or 6th gear, with the handbrake fully on, and using lots of revs as needed.  The car should stall.  If you can let the clutch all the way out, or nearly all the way, the clutch is worn.

[Cyker]

Does sound clutch-related... does your missus tend to hold the clutch in when waiting instead of going into neutral?

If so, it may be the clutch spring has flattened out and isn't pressing hard enough against the disc anymore (Although in that case it would be doing it in all gears I would think?)

My first Yaris had that issue; Felt like there was really bad clutch slip during engagement, esp. when moving off on a steep hill, but doing the stall trick to check seemed to indicate it was fine.

 

Got my mechanic to change the clutch anyway and we found the disc was mostly fine but worn around the outer edge (But still a good 20,000 miles on it or so he reckoned), the release bearing was badly worn and the spring was flattened on one side and pushing the plate in at an angle instead of flat (Which was why the outer inch or so was so much more worn).

Classic case of the clutch being ridden and held in at the lights I was told (Not by me I hasten to add! I put all the blame on the previous owner!)
 

[FROSTYBALLS]

Hello Ian - welcome to Toyota Owners Club.

Moved to the Auris club.

 

[Jane Doe]

Thanks for that guys. I did wonder about the clutch but thought it would slip more when pulling off and such. I would ask the wife about her clutch control but I'll have to pick my moment carefully ;) 

[Artiom]

I had a similar problem (on diesel though) - the discussion can be seen here: http://www.toyotaownersclub.com/forums/topic/172285-d4-d-engine-revs-jumping-during-acceleration/

In summary, my issue was solved by replacing the clutch.