I went to take my emmisions today b/c i figured since i have a big hole right after my cat mayb i would pass (b/c some fumes would exit there)

and i passed the carbon monoxide test but FAILED the Hydrocarbons test...i guess u need a composite score of .80 and i pulled a 2.31 lol.

the car was running at 175 degrees b/c my tune has the fan on at 180 so that was prolly a little contributing (mayb i should revert to the stock tune and run it hotter next time) also i will be ripping off the old american thunder flowmaster catback and putting on a new hooker catback when it arrives in 3-4 days.

Any suggestions on how to pass?

btw..i have Mac mid 1 5/8 headers to MAC 2.5" y pipe and 3" supercat and 3" flowmaster catback(that has a couple holes in it which is soon to b replaced by a hooker catback)

 

The sniffer is based on percentage of emissions not total emissions. This is why a little 4-cylinder producing half the amount of total emissions can still fail even if he produces fewer total hydrocarbons than you.

At any rate, usually a high hydrocarbon count means unburnt fuel, so it sounds like you are running really rich (or possibly worn rings are allowing a little oil into the combusstion chambers). I would fix the hole in that pipe first. Might want to get it scanned to see what the O2s are reading.

 

Look into your EGR/cats being tired.

 

i thought the egr is only on at startup..and what does a bad cat look like inside b/c im putting on a new catback in a few days and ill b able to see inside..(if the 2 honeycombs are still in place arent they doing their job)?

 

egr is on all the time at part throttle

 

I see you failed your test too. I failed mine last year with a 1.19 for hydrocarbons. I knew i failed cause i had to go through the whole treadmill test. The next time I went I passed in the first 10sec on the treadmill with .019 hydrocarbons. In order to pass I put in the stock thermostat and set the fans to stock (220 i think). I also lowered the timing throughout the entire RPM/MAP range by 3 degrees. You might want to try that before you go back.

 

If you're failing for HC's, it's not your EGR system. The EGR system manages NO emissions. Make sure you have a good tune-up (good plugs, wires and clean air filter). Change your oil as old oil will increase your HC's. If your O2 sensors have more than 50K miles on them, change them. As your O2 sensors get coated with exhaust deposits, they'll cause your car to run rich.

 

Hydrocarbons. IE Excess gas/unburnt particles in the exhaust. EGR's main purpose is to reburn exhaust gas a second time. Think about it.

 

Gonna have to disagree with you on this one. EGR does recirculate exhaust gases into the intake durring certain part throttle opperations (and only when warm) but it's puprose is to reduce combustion chamber temps to reduce NOx emissions. It provides absolutely no reduction in H.C. emissions and infact can easily elevate H.C.'s if not functionong correctly. By the way, I'm a California licensed emissions inspector.

 

Well stated in the post above. Exhaust gas contains little to no oxygen, thereby "cooling" combustion temperatures by "diluting" the oxygen available for the burn.