Having issues getting my Blazer to pass smog and I don't have the cash to replace my cat right now. Put new plugs, wires, distributor rotor/cap, cleaned the throttle body, cleaned the EGR.

I looked online and many people said they used some alcohol in their tank to get it to pass. Some people say 99% isopropyl alcohol (rubbing alcohol) is best, other say denatured alcohol is better. I can easily get either so I am looking to see if anyone else out there has tried this and what they used.

Any damage I could be causing?

 

CRC makes an additive thats been around awhile that claims to pass the emissions test or double your money back so it might be worth a try.

CRC Industries Automotive Product Detail

 

i did the "heat" trick when i was younger. had a k5 blazer i ran down to like a 1/8th tank then put 5 bottles in. truck ran like crap and the fuel pump quit working right as i pulled it out of the bay, made absolutely no difference in the readings