Toyota RAV4 Forums banner

1 - 3 of 3 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 · (Edited)
Hello fellow RAV4 owners,

I have a 2003 RAV4 (ACA21) and, since fixing the ECU 'harsh shift' issue, it drives a little funny. The most noticable thing is that the engine RPM drops a bit more suddenly than I'm used to when releasing the accelerator; it's also a bit sluggish in acceleration, especially downhill (oddly enough).

I think the torque converter may be slipping more than it should. Have a look at this graph of engine RPM (purple) vs transmission RPMs:



If you look at the purple line you can see the engine is having a jolly good time gallivanting around on its own, leaving the transmission behind. At one point here - around 420 seconds - the engine is at 2000 RPM while the transmission input turbine is around 1200 RPM, and it takes many seconds for the car to speed up, until at one point the TC lock kicks in and the engine RPM suddenly drops to 1500 in line with the transmission.

The problem is, I don't know what level of slippage is 'normal' for an automatic transmission. Would you agree that this is too high?
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #2 · (Edited)
I guess an alternative explanation is that it should normally have changed gears down to avoid the slippage, but it hasn't. The ECU is reporting that it's in 4th gear throughout the yellow area.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #3 ·
Update: I experimented with reproducing it as follows: accelerate until fourth gear, then let the speed bleed off, then accelerate again. The car stays in fourth with TC slip and lacklustre acceleration. If I depress the accelerator pedal harder then it does downshift to third, so maybe there is some driver error. But I do feel I should be able to get some more torque in fourth without having to downshift, so maybe there is still a TC issue?
 
1 - 3 of 3 Posts
Top