When I got off the freeway tonight my car seemed to idle really low. I am starting to notice when I drive the car on long drives - 40 -50 miles and the car heats up - it idles really low and it doesnt start as easy as it does when its cold. What could be the problem?

1.7 Djet 1973

HUm..

Could be that your Aux air regulator is closing at a certain temp point, but somebody set the idle before it was closed completely while tuning it.

I block the line off to it when I set the final idle speed.

You may have also had a vaccuum link that is opening/closing with heat.

B

Try adjusting the valve's, it sound's like thay may be tight.
My 73 2.0 would not idle when hot started hard hot.
Adjusted the valve's and all was good.

Mine does the same thing. Just the other day it was idling less than 400 RPMs after a 50 mile drive so I adjusted it up to 900.
Now, it idles at 1300 after it warms up. I'm going to try the adjustment like you said, Brad, by closing off the AAR completely.
bruce

I will try adjusting the idle with the AAR blocked and see if that fixes the problem.

Thanks again ~

Is it best toi adjust the idle when the car is warm, say to 950 rpm, or cold, say to 1500 rpm

I've always heard warm. I did it cold once and it was way too low when it warmed because the AAR was open causing the high idle warm up.
bruce

All this FI mumbo jumbo makes me " The AAR multiplied by the Tangent of the quasi-cosine theta of the vaccum pull multiplied by the inverse inverted variable....etc" jk
Ahhh. THe joy of "set-it a-and-forget-it" Carbs.