Failed Emissions - Running Rich?

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Aug 31, 2005
West Chester, PA
Took my rig (85 FJ60) into get inspected and emissions tested last week and it failed the emissions test (living in Pennsylvania)...pretty misearably I might add.

The HydroCarbon Parts Per Million (HC ppm) i was told is unburnt fuel.... came back at 1192 while the limit is 220. Now, this is only at idle. When tested at 2500 RPM it comes back at 109 while the limit is still 220. So I am thinking it is running rich at idle, or the choke is slightly stuck.

Could someone clue me on how I go about adjusting the air/fuel mixture on the Carb. Also, is there a way to tell if the choke is stuck. I feel that my choke is functioning properly since it helps in starting and my idle decreases once i take the choke off.

Thanks for your help,
You can pull the air cleaner off and adjust the choke while watching it. Make sure it opens all the way. You can also look at the linkage and make sure it moves freely on the outside. Just follow the choke cable. The idle mixture adjustment is on the inside of the carb close to the valve cover. It can be hard to find and adjust with the air cleaner on. When you pull the air cleaner it is easier to see then so you know where it is. It comes with a metal plug from the factory so if it is plugged you will have to drill it open. If it is plugged, I would look elsewhere too since another problem could of caused you to run rich.Do some search on here for adjusting the carb. It is better to do it with the air cleaner on.

Once i find this air/fuel mixture adjustment screw, is there another screw to adjust the idle? or do I just put this air/fuel mixture screw all the way in then back it out the 2-4 turns? Luckily the guy running the emissions test for me said he would hook it up to the machine while we are making adjustments to see if we are going in the right direction.

Sorry if these questions are dumb.
Your questions are not dumb. There should be an idle adjustment screw which acts as the throttle stop where the linkage connects to the carb. All should be visible with the air cleaner off.

You may also check to make sure your air filter is good and clean, more air flow = leaner mixture.

Was there any compensation (adjustments made) when you put on the larger exhaust?
All of the mods were done before I bought it....So I really do not know if there were any changes made when it was put on. I will be pulling the Air Cleaner off tomorrow to root around in there and make some adjustments....

Thanks for the help so far.

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