high speed jumping

[BIGBLUE1212]

about a week ago i read in one of the forums that the early new generation 97-99 legacys are 50/50 power to the wheels until 4th gear (im talking about AT of course) where once you are cruising it changes the power delivery to 80/20 or something like that......well.....ive been experiencing high speed jumping and i think its the tranny or whatever controls the distribution of power to not know to switch from 50/50 or 80/20 and it goes back and fourth back and fourth causing the engine to jump 200rpm up and down.....it only does this on the highway doing about 60mph or so.

 

cheers

[WoodsWagon]

I'd look at a torque converter lockup problem more than an AWD problem.

 

I'm also verry disapointed that this thread didn't include a legacy doing 60mph jumps.

[ericem]

Hmm, did you try reseting the TCU? i called subaru and they told me it needs to be unplugged for 25hrs, to be 100 percent restored to factory settings. Doesn't sound like it would be that, but when you put it in third(shift to third so it doesnt pass 3rd gear) does it have the same effect?

[Manarius]

You made a few wrong assumptions. The Tranny is only 50/50 when forced into 1st gear. Other than that, it's 90/10 unless there is traction loss.

 

If it jumps 200 RPM or so, I'd say that the torque converter isn't locking correctly or the TCU can't decide whether to lock it or not. This could be because of the TCU or TPS (Throttle Position sensor).

[Gnuman]

 

I'm also verry disapointed that this thread didn't include a legacy doing 60mph jumps.

 

I'll have to see what I can do about that. . .