Hello everyone,
My check engine light just went on at 92K miles and I took my car to the dealership. After checking the the computer they recommended replacing the O2 sensor and they said the computer may need to be replaced as well. The car doesn't seem to be getting the same gas mileage which would make sense that maybe it is the O2 sensor.

My question is, if I need to replace the computer, should I upgrade it from stock? Would I get better performance? My car is basically stock except for a borla header I put on a couple of months ago. I plan to eventually replace the stock air box and put a better air intake on and when the exhaust goes put on a nice cat-back exhaust. I do not plan on doing anything else with this car. Is it worth upgrading the computer? Any replies would be very appreciated.

Thanks,

Ken

 

Sorry guys! My car is a 2000Legacy 2.5GT limited.

 

I used to have a 2002 L, which under the hood isn't much different then your 2000 2.5GT. My front O2 sensor failed at about 55k miles, and I had it replaced under warranty (got the extended warranty). They also reflashed the ECU for me, saying that there was a new map to fix the problem that caused my O2 sensor to fail.

I honestly don't know if it was 100% necessary, but I did it since it was free. I think it'd cost you an extra $80, or so, if I remember what the service guy told me. In the end, I'd recomend it, unless it was outrageously expensive.

As for upgrades (like the exhaust and headers), upgrading the ECU won't really help quite as much as it would on a turbo car. From a pure performance standpoint, I don't think its necessary for your car. But from a safety standpoint, I'd recomend it. There may really be a problem with the ECU that needs to be fixed.

 

IIRC, theres a recall for an ecu flash anyways(should be for free).