Any ideas? My car failed MA state emissions test due to excessive hydrocarbons. Car is a 1988 Pontiac Fiero Formula v6 (2.8L GM FI).
HC GPM = 2.54 (limit was 2.00) CO GPM = 13.98 (limit was 30.00) NOx GPM = 2.04 (limit was 3.00) CO2 GPM = 188.57
I have replaced O2 sensor, adjusted timing (w/ ECM in diagnostic mode as instructed), oil change w/in last 2 months (Mobil One 5w30, low mileage), cleaned distributor cap & plugs (bosch platinums w/ under
5,000 miles). Plugs were lightly coated in black residue.Mechanic performed emissions test without letting car warm up (does that matter?)
Am not a mechanic but can follow guidance (and really appreciate any advice you can offer on what I should do to pass :-)
Thanks, Bob Levy snipped-for-privacy@rcn.com