Recently purchased a 1991 Sunbird LE, 2.0 OHC car with 145K. Runs great, drives great. Drove 50+ miles home at speeds of 70+mph with no problems. Did a preliminary run-through at emissions, which it failed (Hydrocarbons 286ppm/limit 220, CO 1.53%/limit 1.20%). Subsequently I have changed the oil (it was due) and air filter. Filled up with mid-grade and a bottle of CRC Emissions Pass fuel additive. Will refill and retest soon. Anyone have any experience with these additives and emissions testing?
Also, the temperature gauge does not rise past the 1/4 mark. Is this most likely the thermostat or could it be the sending unit? Thermostat seems easy enough to replace on this model, but what about the sending unit?
Thanks in advance for your help. While I may be more car-savvy than most girls, I'm still not completely " car literate".