I need some help on this one. I tried to go through emission testing yesterday here in Tucson Arizona and failed. I have tried my best to do this resto-mod well, clean, and legal. Anyways, here is what went down,

Loaded test:

HC allowed 220. Me=226
CO allowed 1.2. Me=7

Idle test:

HC allowed 220. Me=577
CO allowed 1.2. Me=8

Facts: brand new exhaust with high flow cat, working air pump, evap canister, and what I believe to be a well tuned motor/carb.

I do not have an egr, as visual inspections are not done.

I know my idle test will be tough to pass with my cam, but whats up with the CO?

 

The bad HC is also causing the bad CO. Engine is running too rich for the cat to handle it. Make sure the cat is well lit up before getting sniffed, and make sure the engine is properly tuned with no misfires. Removing the EGR will cause you to fail the NOx portion of the test. Also it would help if you let us know what engine, year, etc..

 

It is an 87 Iroc, H code so it only has to pass that set of parameters. There is no NOx test only HC, and CO.

it is stroked and bored 350 to 383 (with all other proper machining done) It has aluminum edelbrock heads, aluminum air gap intake with edelbrock EC 750 carb. I do think it was a little rich since it was jetted at sea level and I'm 2650ft.