I changed the cap, rotor, wire and plugs a week ago just after running seafoam through my vacuum line. I've got a 95 auto LS that averaged more than 300 mpg mixed driving before the light came on. Now I'm at 135 and I have under half a tank. Did I clog up my O2 sensor with the seafoam? I mean, I do beat it a little more recently being happy to leave work and drive home, but that's too dramatic of a discrepancy to take the full blame.

Not sure if this affects it, but I'm about 5000 miles into my last oil change (mobil1 full syn) and plan to take care of that this weekend.

 

Did you change your plugs after doing the Seafoam treatment?? You might also want to check your O2 sensor too.

 

Yeah, i popped them in after i did the foaming. Know of a cheap place to get an 02 sensor?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chahsiubow &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, i popped them in after i did the foaming. Know of a cheap place to get an 02 sensor?</TD></TR></TABLE>

If you want a universal 02 sensor, you can get one at any car parts store. If you want a Denso or NTK one, http://catalog.overnightautoparts.com/ has good prices on them.