Hey Guys, on my drive home this eve my 2009 GMC Sierra 1500 5.3 2wd went into reduced power mode, stopped responding to pedal input, started misfiring bad, the trans went into limp mode and the only code the PCM kicked out was a P0066 Air Injector Control Circuit

Once on the side of the highway and stopped, try to restart, still misfiring. Get out, open the hood, everything appears normal, close the hood and restart the truck. It then fires up normal, idles normal, went into gear normal, accelerated back onto the hwy like normal and cruised normal for the rest of the 20min duration on the way home. The CEL still on as the P0066 is a hard code.

When I get home I fired up the laptop, opened up Hptuners, got into the DTC list and P0066 doesn't even exist in the DTC list to check out it's set conditions.

Anyone have any idea what P0066 means in the GMT900 platform, what the hell is an Air Injector Control on the 5.3L? Thank you.

 

You sure it wasn't P0068?

 

Could be associated with o2 sensor issues. Check all your fuses.