okay i posted a little while ago about a code 21 i just changed my spark plugs, and the cel went away for about an hour, then came back on. Is this because i unhooked the battery and it took a little while for the car to figure out what was going on? The only gauge i have in my car right now is boost, i havent installed the others, but im holding back on boosting until i get these in. Ive been told code 21 is the 02 sensor, could i be getting this because im running lean?or too rich?

i believe code 21 is injector #1 control circuit...

Michael 99gs
Boost It!
Mods:
no time to put in yet: s-fmu,injectors, and crane ignition.
Hrc Stage 2
Greddy Type S Bov
VC-2
Road Race Catch Can
Greddy Profec B & Switch
Apexi WS Catback
Super Afc
Autometer Boost,
Egt
Air/Fuel Light & Digital
Tokico Adjust Struts
Eibach Pro Kit Springs
Front & Rear Upper Bar
CarCraft Interior
Sound System= Bring it On

I'd say code 21 is usually just that u have a bad 02 sensor. I've been driving with a code 21 for over 10 months now. doesn't seem to be affecting anything.




HRC Stage 2