Red_Bully

Each time i start my T/A after it being sitting in the garage for the night ... it takes about 5 minutes before my idle drops back down below 1000 rpm. It starts off at like 2100 rpm ... i pump the gas each minute intill it progressivly after about 5 minutes drops below 1000rpm ... Once its been running it seems to start fine and the idle is always below 1000rpm when i start my engine. The problem only occurs when the car has been sitting for a while. wat is the problem here ? Or is this completly normal? (I'm guessing it has to do with my carb hint why i posted it in the forum)

kronos

That sounds like your fast idle screw, it works in conjunction with your choke. What kind of carb do you have? There should be a 1/4 inch screw located on the underside of the choke lever that you can access by opening the throttle to wide open. Turn the screw clockwise to increase idle speed, and counter clockwise to decrease it

spartyon

Every car that I have owned has done that. It's pretty normal for a cold motor to start at a high rpm and gradually fall down to normal idle. My Taurus screams in the winter but in warmer temps nothing. Its all about getting to warm opperating temps quickly.

bilms01

Sounds like the choke pull off isn't adjusted or not working.

Damon

Carbs always have a fast-idle linkage built into the choke system. Any time the choke is on the idle speed will be raised over normal. When the choke is fully closed (cold) it will be highest, although 2100 sounds a bit too high to me. As it warms the idle speed will drop in little steps until the choke gets fully open at which point you will be at your normal curb idle speed.

With the engine overnight-cold, remove the air cleaner assy. Pump the throttle linkage once to allow the choke to close (should 'snap" shut fully). Look under the choke linkage on the passenger side. Pointing forward you will see the head of a screw (usually Torx-head style on computer controlled QJets). That is your fast idle screw and it affects your idle speed any time the choke is on. Once the choke is fully open it has no effect on idle speed.

Fire up the engine and let the idle settle down just for a few seconds. Adjust the screw to achieve about 1500 RPM idle on a cold engine. You only get really one shot at this every morning when the engine is fully cold, so make your adjustment time count.

On a cold day about 5 minutes for the choke to open completely is about right, maybe a little slow. On a warm day it should be fully open in maybe 2 minutes or less even if the engine is cold.

84z28350

Its not malfunctioning, its working perfectly. Just slightly out of adjustment, you need to back off on the high idle screw a hair so it doesnt rev up quite so high. I like to set mine around 1500 high idle.