ALFAGTV6.COM

[valvebounce]

My '85 GTV6 failed PA State emissions.

Two weeks ago...
CO% x liters :: reading was 0.4, limit is 1.1 -- result pass
HC ppm x liters :: reading was 717, limit is 275 -- result fail
NO ppm x liters :: reading was 2720, limit 3600 -- result pass

This is what I did to rectify:
1) Installed a new catalytic converted (the old one was gutted out)
2) Replaced the O2 sensor. Old unit was 0 volts; the replacement oscillates between .1 and .9 volt at idle, seems mostly in the .5 to .7 V range
3) Minor tuneup with new cap, rotor, Bosch platinum plugs, new air filter
4) Checked and addressed any possible vacuum leaks
5) Timing set at the "P" mark according to workshop specs
6) All temp sensors within Ohm specs according to book

Testing today...
CO% x liters :: reading was 1.72 = fail
HC ppm x liters :: reading was 752 = fail
NO ppm x liters :: reading was 3377 = pass

The mechanic did an immediate re-test 15 minutes later, no changes to car:
CO% x liters :: reading was 2.57 = fail EVER FURTHER
HC ppm x liters :: reading was 340 = fail but 50% IMPROVEMENT?
NO ppm x liters :: reading was 2520 = pass

I am very surprised at the wildly different test results within minutes of each other today. Of course, also disappointed that it failed after really trying to run clean. The mechanic said that the car smells rich. I agree, though it is a lot better today than it was before.

The motor has about 122k miles and is a bit smokey. It was last year also but passed emissions with flying colors.

Any ideas?

Thanks,
Edwin

[Mats]

Timing at "P"? Sounds like you set the timing at TDC to me. That can't be right...
And yes, that will give you all kinds of combustion issues.

[valvebounce]

Correction on my note suggesting timing against "P" mark -- timing correctly set at "F" marker.

[Zamani]

Check your valve clearances. The exhaust, I believe may tighten up.