Car ('84 242 turbo) passed emissions last January with flying colors (well CO was borderline in the 25/25 test) after a major tune-up. HC was half the allowable ppm, NOx was 1/3 the allowable ppm and CO% was .94 (1.00 allowable) in 25/25 and .27 (.91 allowable) in the 50/15 test. It was cool (Atlanta weather in January, probably in the 40's).

The car sat for most of the spring and summer without a tag but I now need it for a commuter. I just had it retested (they will not accept the test from January) and it failed in both HC and CO, NOx was very low (much more so than in January). It was very hot when tested (90's). I have done nothing to the engine or components (Ign., fuel, etc.). I did R&R the clutch and had the exhaust system out of the car. It starts and runs smoothly and has good power, nothing untoward that would indicate any problems.

Could the cat have gone south because I was moving it around while doing the clutch? Would it result in CO readings 6 times the allowable and HC 50 ppm over the allowable in both the 25/25 & 50/15 tests? Or is there something more obvious I am missing that would result in this radical change in emissions output?

I'm going to check for vacuum leaks, ign. timing and such in a few minutes but thought I would put this out there for the guru's to mull over.


'94 945T (daughter co-opted it for college, used to be mine)
'99 S80 (mom-in-law's)
'88 240DL (son's)
'84 242Ti (future commuter)
'89 560SL (wifemobile)
'88 300TE (my commuter, for sale)
'68 GT500KR (under restoration)
--
Bob K