Passed CA Emissions

[Hib Halverson]

Originally Posted by Z51JEFF

Well,just got back from my friendly neighborhood smog nazi and my Haibeck chipded,other wise 100% stock 18,000 mile 1991 ZR-1 FAILED!On NOX I think its 702 with a 502 max.So whats my solution here guys?Drove the car for 20 miles right to the smog station.Stock chip,octane booster and what brand of gas Im not sure.How do I get this this thing to pass?

Wow...that's failed by a ton!

Unfortunately, if the engine is running right, 90-92 owners have few options as far as EGR because they don't have an EGR valve. Plus the State of California wants to force old cars off the roads and one way it does that is by lowering the emissions limits which has been done at least twice since 1995.

First, stop using octane booster. Few of them are effective and the ones that are (which use MMT as the active ingredient) can damage your cat converters.

Specifically, what brand of octane booster have you been using?

Secondly, I'd inspect the engine looking for anything that will increase combustion temperature which raises NOx emissions. Check the engine over and report back to the forum on your findings?

Lastly, can you post the full results of your test?