I took my 94 Full size Blazer with the 350 to get inspected today, and it failed the emissions test. It failed due to High Hydrocarbons on low speed (idle). Everything else passed. What whould it take to repair this. I'm thinking EGR valve, but possibly what else. I replaced all the plugs and plug wires a few months ago. They looked good.

I failed on Fri for nox and was told that 'cus of my egr.

I would look into a new Cat...I mean if you still have the original in...it's probably time, try to scan it for codes, see if you're O2 sensors are working. Run some injector cleaner. I don't know if the 94' is the new fuel injected GM motor or not. EGR could be it too. If it's the newer style motor, you should be able to replace that yourself.

Simply put, whats cheaper, a new truck or a little bit of $$ for passing smog. You got to pay to play.

Probably the cat. EGR is mostly used to reduce the NOx levels.

From my understanding the catyltic converter serves as a cataylist to convert CO to CO2. Its secondary function serves to reburn unburnt hydrocarbons. If you've got excessive hydrocarbon levels, changing the cat. may not solve your problem by itself. It may also just plug up with more hydrocarbons and soot before you fix the real problem.

My 0.02