Failed Emissions Help

[FrostyCVW9]

I recently acquired a 1974 914 2.0 and just failed emissions. Idle HC's were 439 and the allowed max is 400. I feel like I'm close. Any help on adjusting the fuel mixture leaner would be much appreciated. I believe it's as simple as counting "clicks" on an adjustment screw in the lean direction, but I don't know where that magical screw is located or which direction is lean and which rich. Thanks!

[Dave at Pelican Parts]

Idle HC is adjusted with the knob on top of the ECU. I believe that left is lean, and right is rich.

Make sure your ignition system is in tip-top shape as well. I had ignition points that were not in great shape and it really threw my emissions out of whack!

--DD

[jess p]

Additionally, add a few pints of straight ethanol to your gas before you go to emissions. No more then 2 pints.

[bowlsby]

What state/jurisdiction tests a 1974 914 for emissions? I thought they were exempt everywhere by now.

[FrostyCVW9]

Thanks for the pointers, fellas! Good to have this information. After a bit more research into testing regulations, I found an exemption for classic cars, but it required me to drop the 914 from my conventional insurance and get “classic car insurance” which I got at Haggerty. Appreciate the comments. BTW, jurisdiction was Tucson, AZ. For no restrictions, cars have to be 1966 or earlier to have a full emissions exemption. Rural registrants also have exemptions.

[dr914]

maybe a leaking pressure sensor

[mitchhy]

To adjust the fuel mixture on your 1974 914 2.0, you’ll want to locate the fuel mixture adjustment screw, which is typically found on the fuel injection unit

[azbanks]

@FrostyCVW9
Welcome to the bird board from a fellow Arizonian. I am north of Phoenix.

[Tobra]

I have had an oil change bring my HC down