Ally4355

Update: I replaced the battery terminals and the check engine light has not come back on....YET. How long does it usually take for the computer to reboot and throw a code?

Thanks for all the suggestions! I'm going by start by getting new battery terminals today and I will go from there. Has anyone had any complications doing this to their battery? http://www.thediyguy.net/2013/09/how-to-replace-battery-terminals/ Also I did get the NGK brand plugs and wires about a month ago. But they already seem to be bad. I think whatever the problem is makes them go bad almost instantly. I want to try and fix the problem before I go buy another set as to avoid wasting another pair.

Need some advice, I have a Subaru Outback 2000 with over 250,xxx Miles. Codes: P0420 and P0303 When I initially ran the reader it said the O2 sensors were bad, both front and back. I replaced those hoping it would eliminate the 420 code also but it has not. Though, the O2 sensor codes did go away. Any advice on what would be good to check before outright replacing the Cat? As for the 303 code I was advised that this is probably related and will go away once the 420 code is eliminated. The car doesn't run well. It lacks power and often stutters while accelerating, sometimes almost violently if the AC is on. My Battery has had some issues with a bad connection that I have to tighten frequently because someone overtightened it. Anything helps!