Fail Emission - CO too high - help

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Mar 5, 2003
Seattle, WA
OK, fail the emission.  CO is about 4.5 above limits at idle.  I need help before spending $$ with a mechanic.  Here's what I've done so far:

1.  changed plugs
2.  changed wires to 8mm
3.  spray clean the carb
4.  changed oil

to do list:

1.  caps and rotor on order
2.  replace air filter

What else do I need to do?  The previous owner had the idle too high so I adjusted down.  The computer reads about 610 - 630 rpm during the test.  Will adjusting the idle up to like 800 rpm and changing the air filter will bring down the CO?  Thanks for any tip(s).

Sorry, it's a '78 with the F engine.
check your timing. You may be able to retard the timing a little to pass. &nbsp:Does your mechanic have a gas sniffer to help with the tuning? You may also need to adjust the idle air screws on the carb.
I think I have posted this before, but my business partner is a muscle car guy and has compiled a lot of emissions testing info. He setup a page at

He has lots of tips and tricks for passing.
Lean it out and rev it up. If all else fails, move down here to Alabama! :D

Missions? You must be crazy, boy! Only kinda missions we got is tryinta get tha shine past ole Roscoe an inta tha dry counties!
change your pcv. Also check for cracked or warn out vaccuum lines and that your cheke isn't stuck. Before your next check take the care on the freeway and make sure it is well warmed up just prior to the test.
If you search TLCA you will find a few write us onwhat else to do.

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