gardorr

I've actually hooked up a monitor and it's running lean when it's not running well.

I already tried replacing the knock sensor, but it didn't change anything.

Once it starts acting up it doesn't stop until you reset the ECU. So even if I let it cool off and then started it back up the issue persists.

No codes and it has a fresh rebuild on it. Everything been replaced including the head gaskets.

Nope, I don't have a check engine light on. I even scanned it to make sure there weren't any soft codes.

I have a 1999 legacy 2.2 that is sluggish, lacks power and sputters until it reaches about 3300 RPM's, then it's like something kicks in and the cars runs great. If the car is allowed to cool off and you reset the ECU (Unplug the ECU or battery) the issue temperately goes away, but after running for approximately 20 - 30 minutes, the issue slowly returns. Any idea's?

I have a 1999 legacy 2.2 that is sluggish, lacks power and sputters until it reaches about 3300 RPM's, then it's like something kicks in and the cars runs great. If the car is allowed to cool off and you reset the ECU (Unplug the ECU or battery) the issue temperately goes away, but after running for approximately 20 - 30 minutes, the issue slowly returns. Any idea's?