I failed emissions on high hydrocarbons, however my CO, NOx and CO2 are high as well but I passed on those.
HC 1.86 GPM
CO 24.97 GPM
NOx 1.87 GPM
CO2 411.69 GPM

For the past 3 times I have gotten my car inpected since 2000 my levels have risen. In 2000 my emissions
HC .1246 GPM
CO 1.09 GPM
NOx .1242 GPM
CO2 37.93 GPM

A year and a half ago I installed a new high flow catalytic converter since it was clogged badly, a K&N open element, 160 degree thermostat, new plugs, wires, cap, rotor, fuel filter, and pcv.

I am now going to replace my wires, check the plugs, replace the oxygen sensor, pcv valve, clean my fuel injectors, and check my vacuum lines.

Anything else I should do? Should I replace the stock air filter assembly and thermostat to pass as well? What is the exact size of the vacuum lines if I need to replace them? Thanks for your help.

1990 305 TBI 158,xxx

 

correct me if I am wrong, but I think the hotter the engine, the better (cleaner) it will burn fuel. I'd throw the 195* back in, and make sure your timing is set properly. Just my suggestions.

 

The warmer engine temp would definitely help. Do you still have the EGR and AIR functional?

 

yip dump the thermastat and put in the stock one then change it once you pass

 

Get the engine and cat to temp. More importantly, what is the state of tune? O2 age? etc.

 

The O2 sensor is 5 years old. I did warm up the engine by driving around for a good 20 minutes. The last tune up was 1.5 years ago, about 15,000 miles. The AIR and EGR are still hooked up. I'm not sure if they are functioning correctly. How would I check that, I don't have my Haynes manual with me.

 

I'd start with that O2 and stat then and also check timing, inspect cap/rotor etc., air filter etc. It may be your state of tune, you may have a bad or fried wire etc.

 

Ill bet if you change the stat, it will pass. This is one of the main offenders in a emmission test.

 

I'm betting heavily on the T-Stat and O2 sensor solving your problem. The O2 sensor being the biggest culprit.

 

Thanks everyone, I am going to replace the O2 sensor and thermostat and go in for a retest. Will let you know how it goes.

 

Just for laughs, I would check out the EGR valve whle you're under the hood.
start the car and hook up a vacuum pump to it(like the ones you would use to bleed brakes) if you put vacuum to the egr while the car is running, and it stalls out then you know the egr is functioning. If it doesn't it means the egr isn't working properly.

 

Ya know, these so called emission test are so full of crap. In my lovely state of Pa., we must have 5000 miles or less, and we can get an "exempt" sticker. Now, I have no problem with that. But for all the cars that actually have to be tested, #1 you must pass a "visual " inspection, making sure all of your smog equipment is on the car. #2, you must have your fuel cap pressure tested. Now the part I feel is wrong is,...Lets say I fail because I have no cats on my car. Another guy with a 1981 Ford Escort, has the cats, and passes the "visual", but his cats havent worked since 1990, or are "hollowed out". So technically, I would have to purchase new cats. just to pass the "visual", just like the guy did with the "non working" cats....Dont get me wrong, I love clean air, but lets not be biased towards performance cars, and be fair. If one guy needs the cats, everyone should have his car meet the standards too. Somthing to think about the next time a station gives you crap about your car. Also the trucks that buisnesses use in Pa. are also exempt...Thats right! Vehicles on the road everyday being exempt!...Tom

 

Well I put in my old thermostat, replaced the O2 sensor and replaced my wires. I got passed emissions but just barely on hydrocarbons. Thanks.

 

big siiii of relief i bet

 

if u want to make sure it passes buy some SEAFOAM avaible at nappa. I haven"t failed yet