Me and my Mom were coming home from dinner on the freeway tonight when about 6 miles from home, "DING", the check engine light comes on and I'm losing power fast. Get it off the freeway and she's still running but sounds like an old farm tractor. Hook up my Smarty and get code "2146 unknown code". Clear it twice and it comes back right away. I limped it home to where it now sits. Can anyone help? I've had it on the stock setting for several months now and has never given me a problem in 6 1/2 years and 91000 miles until today. 2006 2500 2wd.