Infrequent Idle Help!!

[blakem7106]

I'm having issues with my idle, it's jumping around between 600 and 1000 rpm all new plugs, dizzy,leads, coil, points, rotor, reconditioned carby about 8000 kms ago. What would be causing it?? Would it be vacuum related?

 

By the way it's a 1978 ke55 4kc with a 5 speed

 

And after market air filter and I changed the oil/filter about an hour ago no difference

[altezzaclub]

all new plugs, dizzy

 

So that means an actual new distributor??

 

How long has it been doing it?

 

and how did it start? Gradually, or suddenly?

[blakem7106]

Yeah new dizzy and only noticed it a few days ago. And first thing in the morning runs fine cold but as soon as it warms up the idle jumps around

[altezzaclub]

And first thing in the morning runs fine cold but as soon as it warms up the idle jumps around

 

I was thinking wear in the dizzy shaft, but obviously not. That quote make it sound like an air leak, so the choke covers the lean mixture when cold but when its warm the lean mix nearly kills it.

 

Have you had a go at the idle mixture and idle speed screws? Check around the inlet system with an aerosol or a tube in your ear. Inspect the rubber tubes on the vac setup. Swing a spanner on the manifold nuts. That 2-piece gasket on the stock 4K manifold is a scene for disaster I reckon, although mine was leaking out the exhaust and not in the inlet.