Subaru Problems? Ask a Mechanic for Answers ASAP
Pull the front O2 sensor out of the catalytic converter and see if the car runs better. If the substrate is broken up and blocking the exhaust it will run fine at idle, but have a lot of trouble under load. Removing the sensor opens up a hole for the exhaust so if it's blocked it will run better and have more power.
If it does, then the converter s the problem.
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