Mechanics

POOR ENGINE PERFORMANCE AFTER CLEARING CHECK ENGINE LIGHT (FOLLOW UP TO PREVIOUS QUESTION)

1999 Subaru Forester • 184,233 miles

As a follower up question. Whenever I start the car, it runs poorly has no acceleration. It appears that depressing the Gas pedal causes worse performance. The muffler also runs with a puffing sound.I remove the upstream Oxygen sensor and perform a heat test on it an it seems to be OK. I also tested the downstream O2 sensor before I replaced it. This one did fail my heat test. Could the timing belt be causing this problem?
Original Question ( had $10 donation):
Vehicle - 1999 Subaru Forester AWD had the following check engine error codes: P0170, P0463, P0130, P0136, P0301, P0302, & P0303. I disconnect the battery, reconnect battery which clear the codes. Now the car seems to have no acceleration power. If I press the gas pedal the rpm jumps up to about 3000 rpm and drops to below 1000 rpm and the vehicle has no acceleration power. I changes the downstream oxygen sensor, the PVC valve and the 2 air filters, sprayed the MAF sensor with MAF cleaner to clean it but
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Baemr
December 13, 2011.



First, you need to find out the exact fuel pressure.

The cat converter may be clogged causing a restriction in the exhaust. With the missfire codes, did you replace the plugs?

Roy

ASEMaster6371
Dec 13, 2011.
The subaru was running much better( It would hesitate a little before accelerating) before I disconnected the battery which reset the check engine light codes. The puffing muffler problem started after the codes were reset. About the plugs; I will remove/check and replace the plugs and then check the fuel pressure if my local auto parts store has the equipment for checking the fuel pressure.

Tiny
Baemr
Dec 13, 2011.