My 01 Legacy Outback Sedan with 118,000 recently started acting up. Some times it will drive perfect and other times it acts like it is not getting any gas. It will sometimes stumble and hesitate when accelerating or will run rought at idle, and at other times will run fine. I have been told it is the TPS (throttle position sensor), or the fuel pump, or the IAC (idle air control). Anyone have any experience with this problem? Thanks, RC. (respond to me at rcglfr@comcast.net.)

My 01 Legacy Outback Sedan with 118,000 recently started acting up. Some times it will drive perfect and other times it acts like it is not getting any gas. It will sometimes stumble and hesitate when accelerating or will run rought at idle, and at other times will run fine. I have been told it is the TPS (throttle position sensor), or the fuel pump, or the IAC (idle air control). Anyone have any experience with this problem? Thanks, RC. (respond to me at rcglfr@comcast.net.)

 

My 2002 Legacy GT had the same symptoms. Things got really bad on the way back from work one day at around 75,000km, when the engine would jerk violently out of first gear, show total lack of power, even jerking at highway speeds. The dealer eventually found the problem - a bad knock sensor. The heavy jerking caused the exhaust header to crack on one side. Subaru Canada came good for it. Lately (142K) I've noticed a bit of hesitation under hard acceleration. A co-worker with the identical car did some research and says this is due to a poor air inlet system design. I don't have much confidence in the Subaru drive train anymore...

My 2002 Legacy GT with 40,000 miles has a hesitation to accelerate from idle so I am watching this thread with interest. I'm assuming that the bad knock sensor on scarlet27's engine didn't even trigger the check engine light.

 

I haven't had mine into the dealer yet as I'm going to replace the spark plugs, spark plug wires, fuel filter, PCV valve, and O2 sensor on my own and see if any of those make a difference. I discussed the idle hesitation briefly with the service manager at the dealer and he said that mine might be a candidate to have the ECU reflashed. I need to do more reading here on the forum about this, but am really interested in anyone's thoughts on a fix to idle hesitation.

 

Thanks,

 

Pacey

My 01 Legacy Outback Sedan with 118,000 recently started acting up. Some times it will drive perfect and other times it acts like it is not getting any gas. It will sometimes stumble and hesitate when accelerating or will run rought at idle, and at other times will run fine. I have been told it is the TPS (throttle position sensor), or the fuel pump, or the IAC (idle air control). Anyone have any experience with this problem? Thanks, RC. (respond to me at rcglfr@comcast.net.)

 

Check engine light on? Pulling codes is the place to start.