Running lean at idle

[ir3333]

...Seems every time i solve one problem another crops up.
Came home from a road test and and noticed the wife was filming so i stopped and did a burnout.
Now the idle is very lean and it runs rough...if i give it throttle it richens up but is not running right
..your thoughts?

 

[ir3333]

bump
will misfiring cause a lean reading?

 

[RedFish]

could be fuel delivery. If carb is overheating the delivery can go into repeating lean cycles. Easily seen with a clear fuel filter mounted horizontal near the carb.

 

[ir3333]

no, i ran it after engine had cooled down and it was still lean.
just rebuilt carb and everything was running perfect?

 

[mderoy340]

Check the throttle plates and make sure they are closed at idle. Since you did a burnout I assume you buried the pedal. Have someone push the pedal to WOT and check for smooth throttle operation.
I had a carb holley VS do this every once in a while after a hard run at the track. The secondary plates were not fully closed and screwed up the idle AFR. I had to remove the carb and center the rear butterflys.

 

[ir3333]

O.K. for those that may have a similar problem some day.Rem'd carb and gently blew
and cleaned the idle mixture,metering rods and jets.
Re-assemble with gaskasink and fired her up.
idles O.K. but haven't road tested yet
...hopefully a bit of dirt or a small vacuum leak..this new eddy has given me fits