engine and drivetrain Tii Question on fuel air ratio

[Tiger75]

When an engine hunts at idle i.e. changes RPM over a narrow range,

Is this due to a fuel air ratio that is too lean?

[_z_]

many times hunting is due to an air leak in the intake somewhere

[ray_]

What _z_ said...

... but it's also possible a CO adjustment via the screw inside the tuna can will rectify things.

Cheers,

Ray

[dubois]

In addition to air leaks, your linkages also play a part; any play in any of the links between the the pump and the air throtle, has the effect of altering the a/f ratio within a narrow band.

[JR]

I had similar symptom on my 74. Searched hi and low for vac leaks and found none. Slight tweak to make idlr more rich worked. Wish I had a CO monitor to really ck it out.

[BillWilliams]

place will allow you a test without consequence.

That will give you CO reading

[peteinjp]

Be very sure that the timing is correct. If I remember there should be no advance at idle. This could make Any way, If you haven't already check that the ignition is in spec because this can cause or help to cause hunting as well. Linkages and Thottle body synced check for air leaks. Then if its still hunting make the idle adjustment a tad richer and see if that doesn't do it. On my car the no hunting setting was within the factory spec in terms of CO output.

Pete