Just had my rad replaced after discovering I had no coolant left! I appear to have been very lucky and pulled up before the temp got too high and fried everything.

New rad, car is now running lovely, staying at a nice temp.

, pulling well, no mayo under the oil cap, but it won't hold it's rev's on idle.

It idles fine at first

(800-1000) then slowly drops and drops until it's about to stall.

Any idea's as to what might be up?

(please be gentle

[-o<

)