Emission adjustment to reduce CO% in NJ

[Robert911]

My 1980 911 SC (CIS) failed emissions in NJ. The standard reading for CO% should be 3.0, my car was reading 5.1. Does any one have any suggestions on reducing the CO% emission?

[VincentVega]

I just failed with my SC in MD. First suggestion is a general tune up, check plugs, valve adjustment, air filter and so on. If that's all good you might need to lean the car out via the fuel distributor. This is best done with a gas analyzer, I just ordered a Gunson, to get get it right.

Best of luck!

[fred cook]

Robert,

I also have/drive a 1980 911SC. I have seen recommendations for CO settings from 2.0-3.5% at idle (before the cat). I currently have mine set at 2.0% where it runs well and gets decent gas mileage (18 in town/27 on hwy). The Gunson GasTester is a reasonably priced and useful piece of equipment. I bought one right after buying the SC and have used it successfully to tune my engine. The one that I bought was the basic unit which cost about $125.00. You will probably find that resetting your engine's CO to the 2.0-3.5% range will make the car run better, get improved gas mileage and pass the inspection!

Good Luck

Fred Cook