Join the community and post your question. Use our Ask-A-Tech for free now! ASE experts standing by.

Forum > Failed Smog Test > Question

1977 Chevy Blazer 305 V-8 motor failing high CO. Why?

My 77 Chevy blazer has a rebuilt 85 305 V-8 with 35+K on it already and Car converter. It has passed emissions test 3/4 past years perfectly - after the cat installed. Last fall I had a carb fire and had to rebuild the Edelbrock 1406 carb, not it fails on CO at LOAD test...even after rejecting it from .095/.098 to .080./.086 with .041/.062 rods and 3 gal of E85 fuel, and 1 gal of denatured alcohol - it still runs 4.84 and should be less than 3.0. What gives here? I am as Lean as can be with it now.
Answer:

If you are absolutely certain the carburetor is adjusted properly, we can only suggest looking into other sources of fuel entering the combustion chambers... such as the EVAP system. Perhaps your Chevy's charcoal canister is saturated. We also recommend conducting a fuel feedback test if this engine's fuel system is electronically controlled. posted by SmogTips Support

Related questions and answers you might find useful:

Your Instructions make no sense by GARY

How Do I Get a Smog Check Waiver? by Margaret

Do I Need a Smog Check This Year? by Joy

Mini Cooper DMV Registration Due in 5 Day Won't Pass Smog by anne

1995 BMW M3 Gross Polluter High HC & NO @ 15MPH by Jared

View SmogTips.com in: Desktop / Mobile