My 91 Lo3 Camaro has barely failed California's emissions test but, last year it barely passed with a new Cat and increased fuel pressure.

I haven't changed any settings since last year so, I was wondering should I use Denatured Alcohol and how much should I use? I bought a gallon of Denatured Alcohol and was wondering if I should pour the whole gallon in a full tank or just use a quart or so?

 

man, welcome to the club, im very interested in this too, i dont know how much they expect me to pay to get this damn thing to pass, im a full time student at Cal Poly and definately dont have the money.

 

Well, I poured in a gallon of Denatured Alcohol in a nearly full tank of gas and took a re-test. The car failed again but, everything passed except the HC. I think the reason is because I increased the fuel pressure too much when I did the exhaust and open element.

I decreased the fuel pressure back to the original setting and actually the throttle response seems quicker. I still have 3/4 of a tank of gas with the Denatured Alcohol in it so, I'll have it tested again hopefully for the last time.