92 Camaro RS 5.0 failed CA emissions, NO PPM too high

"D" wrote: > Hello, > 92 Camaro, 141K miles, 5.0 V8. Throttle Body, NO PPM @15 mph > max 772, ave 237 Meas was 871. > Never failed smog in 12 years. Recently replaced EGR valve, > the diagnostic code showed egr failure. No other codes are > present. > The HC was pretty close, Max is 110 and Meas was 109. > Car was totally warmed up. > Any suggestions as to how to make it pass smog? > > Thanks. > > D.

The timing was off. S/B 0 degrees and it was at 3 or 4. Adjusted the timing and the NOx fell within range. So there you go.

Hmmm,

Sounds familiar. I offer few suggestions.

1. ChaNGE THE OIL - believe it or not this helps more than you'll ever know

1. PUT HIGH OCTANE FUEL IN IT- this will inerently lean out the mix

2. CHANGE THE EGR AGAIN - you could have gotten a bum valve

1. CHECK YOUR CAT, IT'S PROBABLY TOAST - check for "carsound" cats, they are around 60 bucks.

2. If you hear noisy valves, they may not be closing all the way. Could be cam or burnt valves. Passenger side tends to go first. A clue is if you are adding water a lot. If you are, it is time for a valve job. My 90 is in the shop right now for it. That is 2400 out the door.

Good luck

Jim