Hello.
I replaced cat converter 2 yrs ago to bring down HC in wife's 81 VW Scirocco. Now the car's failing due to high HC again, with only about 2800 miles since last test! Results:
15mph, 1807rpm HC max: 162 - HC meas: 149 CO max: 1.09 - CO meas: 0.27 NO max: 1227 - NO meas: 98325mph, 1938rpm HC max: 132 - HC meas: 172 FAIL CO max: 1.09 - CO meas: 0.27 NO max: 1227 - NO meas: 791
The car is driven every few days for short trips except was driven about
15-20 miles on the freeway before the test. Also, tester ran it for 2 minutes at 2K or so before starting the test. It has over 250K miles and does pass some oil - about 1qt every 200 miles or so I think. It doesn't smoke in normal driving though, and near-new plugs look toasty-good.Question: I put a bottle of Techron in the tank. Is there a chance running that out on the freeway would clean up the test results, or is a new cat the answer? (Can a cat go bad in 2800 miles?!)
Also: what effect does Techron have on a smog test? Does it all have to be run out and refueled before testing?
thx, nf