2004 Outback 3.0L 6 Cylinder Jerking/Losing Power

[FellFromStars]

I have a 6 cylinder 3 liter 2004 Outback LL Bean edition with an automatic transmission that has been having some trouble lately. Often times when going up hills the Subaru will start to jerk and lose power. This also occurs when traveling on level ground after the car has been running a while. The problem started to occur after I traveled for several days pulling a small U-Haul trailer. It started having idling problems where it would rev and then almost stall and then rev again so I left the battery unplugged to reset the ECU and when I plugged it back in, the idling problem was fixed and the jerking problem seemed to disappear with it. However, the jerking problem has slowly come back. There is also a loud thud that has started happening when the car shifts lower gears. In addition the check engine light is on and has been for a while. It is due to a bad fuel censor that was replaced. The light however, never went off.

 

I have read some threads where some Subaru owners have had trouble with blockage in the cat converter but my car only has 50k miles on it so it seems like that shouldn't be the case.

 

If anyone has any suggestions or is aware of a similar thread discussing this issue I would appreciate any help.

[FellFromStars]

I must also note that while power is being lost, the RPMs of the engine do seem to change.

Edited July 1, 2012 by FellFromStars

[CNY_Dave]

Hit autozone or the like and have them pull codes.

 

I think the '04 is throttle-by-wire, on my ;03 similar symptoms were caused by the throttle position sensor, but if you have TBW, you don't have a TPS.

[idosubaru]

TPS - you can probably google plenty of information about H6 TPS's.