Need some group thoughts here...
Having a problem with an idle that holds around 900, drops to 700, back to 900, etc....
I've adjusted my throttle body, adjusted the valves, changed the plugs, timed the motor, and checked for the obvious vacuum leaks. Cap in rotor appear to be in good shape, and it don't think I'm getting a miss.
So I need some advice on where to look next. Fuel pressure regulator? AFM? Anything?
Thanks!
Surging idle
Timing, plug the vacuum lines, 2200 rpm ( good to have somebody on the pedal ) is the place to start. After that set the big screw under the throttle body to 800-1200 when up to temp. 800 is a dab low for my liking although spec.
If you get searching on warm up, it starts, finds 2000 and gradually drops as the temp needle rises or zooms and drops, it's most likely a gooped up aux air valve. On '79's it's a pain, '81's it sits up on the valve cover.
Its job is to restrict air flow on start. Rust and crud builds up inside to make the piston or disc stick, not do its thing. Too much air lets the idle zoom until it hits the idle cut off switch, to send it back down and start over.
If the idle is goofy warm, at normal temps, that's usually AFM, vacuum, sensors, bad grounds anywhere, distributor sticking, ( Google search the subject here and read FAQs. )
If you get searching on warm up, it starts, finds 2000 and gradually drops as the temp needle rises or zooms and drops, it's most likely a gooped up aux air valve. On '79's it's a pain, '81's it sits up on the valve cover.
Its job is to restrict air flow on start. Rust and crud builds up inside to make the piston or disc stick, not do its thing. Too much air lets the idle zoom until it hits the idle cut off switch, to send it back down and start over.
If the idle is goofy warm, at normal temps, that's usually AFM, vacuum, sensors, bad grounds anywhere, distributor sticking, ( Google search the subject here and read FAQs. )