Expert: Sean Halliday - 2/5/2007

Question
I have a 1993 Nissan 300ZX. 172K miles. Maintained by a friend who happens to be a Nissan shop foreman. Every two years here in NJ it has trouble passing emissions. HC sometimes high, then Nox. The car runs great, no mechanical problems. My friend suggested Justice Brothers fuel injector gas additive as a way of getting through inspection, however that failed too, not by much though, as I passed everything but HC. 120 needed 157 recorded.
I may consider puitting a new cat. converter, but thats not a guarantee either.
I know this may sound wrong to do, but is there anything I can do, even another gas additive, to get this through inspection without requesting a waiver from the state. They bust balls here in NJ and I don't trust their machines at the state level. I think they really want this car off the road and it ain't going to happen.
Going to a private garage is also an option but they will rape me with repair parts, I am sure.
Jim

Answer
Im afraid its a new cat as the NO is usually too high when its done.HC also is affected by the cat so looks like you will have to fork out what they charge for one.Here in California is as bad.They are anal about the smog.I have a toyota celica 190000 miles and the engines a 4 cylinder 2000.they call it a gross polluter.....so ...think youre bad...and the car runs great but you gotta keep them happy so a new converter will lower the emissions by a huge margin.I have used the gas additives on borderline cases and it works but your reading is too high for anything.Try online to buy the cat as it is a lot cheaper for your car than a shop.Then all you have to do is find somebody who can weld.So good luck and i know its a pain i deal with it day in and day out emissions and check engine lights for ridiculous sensors that dont affect the engine at all.