MUKAK

i have a 89 Jeep Cherokee 4.0 inline 6 all stock other than Tires and Suspension, 275k miles on original motor and still running strong!!

needs a smog check, 2 years ago it passed but barely ( according to the Smog Check guy )

i am ready to smog it this month, did basic tune up and was wondering if i add some TORCO to the gas prior to Smog Check will it help or hurt the SMOG NUMBERS

LDB

I assume you are talking about TORCO octane booster. I looked at their web site and they claim 1 quart in 5 gallons will raise octane from 91 to 105. That is impossible from any normal hydrocarbon since the dilution would mean the TORCO would need to be well over 200 octane. Ain’t no such thing. So I looked at the MSDS (material safety data sheet), and sure enough, it is MMT, an organometallic. All organometallics are catalytic converter poisons. MMT isn’t as bad as lead, but it’s not good either. If you are nearly failing smog, it is probably because your catalytic converter is getting weak, so that would only aggravate the problem. Once you have enough octane to avoid knocking, additional octane doesn’t affect emissions, so you don’t get any benefit that I can see. About the only thing you can do short of getting a new converter would be to make sure your car is thoroughly warmed up prior to the test, and don’t let it sit around very long before they test it. Cold engines and converters emit more than hot engines and converters.