when i start my truck it idles really high, like 1500 rpms, until i press the gas petal a little bit, then it will idle perfect. in park and neutral, it idles perfect but, when i put it in gear it almost dies because the rpms drop right when i put it in gear. so i have to put it in and press the gas petal at the same time, so if i come to a stop with out putting it in park it dies
Oh yeah i =ts a 1982 f100 302

 

Its called a "high idle" or "fast idle" it is supposed to do that. It is the choke working.

You need to let it run in high idle or a bit and then kick it down via the throttle linkage and mess around with your mixture and curb idle screws until it reaches the specifies rpm on your emissions sticker. It is about 700 for my Ford man trans, and I believe 800 or 900 for an auto.

The reason I know this because I would start it up and proceed to lowering my rpms and mixture screws I'd hit the gas and it would die. What I was doing is lowering the fast idle rpm and then when I kicked it down it would die because the rpms were so low.

 

thanks glovemeister, ill go mess with it right now.

 

I have been having the same problem for a while. I havent been able to figure it out. Today the truck started and ran ( high idle) then when the choke plate opened all the way it died. I let it cool down and restarted it and when i turned in the idle mixture screws 1/2 turn the truck stalled. Havent been able to restart yet.

 

Ak, what I would do is while the truck is shut down, turn the idle screws all the way in until they lightly bottom and then back them out (equally) 1.5 turns. That should get you running pretty decent. Then fire it up let it warm up for 5 minutes, kick it down (while you are under the hood). Then if you have to keep messing with the throttle linkage to keep it running while you richen the mixture. Do that until it runs pretty decent then set your rpm idle screw.

 

You make a cold engine run by running a richer than normal mixture, the choke does nothing but decrease the airflow so it pulls a greater amount of fuel compared to air into the engine.

When you turned the idle mixture screws in you leaned it out, which is why it stalled.

You can loosen the three screws around the choke cap and turn it counter clockwise some to allow the choke to stay closed longer so it doesn't die when the choke plate opens.

That is assuming the idle mixture is set and working correctly, a malfunctioning idle circuit can be covered up by the choke; until the choke opens and the high idle is kicked down the engine.

 

Thanks. I will try that tomorrow. My battery is charging now. I amy start from the begenning with the choke and all the other stuff on the passenger side. I will just try to follow the directions on my carb rebuild kit and see what happens. If i have to turn it out more than 2 turns i will need to start looking for a vacuum leak. I dont have any emmisions equipment on the engine so im not sure if i have all the hoses correct.

 

It started right up this morning and ran really good for a few minutes. Once i kicked it down it stalled. I dont want to mess up what i have set right now so what should i tweak to keep it running? It even ran good when in gear until it warmed up all the way.

 

Turn in the idle screw, not the mixture screws. The fast idle adjustment overides the basic idle screw when engaged. If your idle screw isn't holding throttle open enough, as soon as you kick the fast idle off it doesn't have enough gas to run. Idle mix and idle screws are completly different things.

 

The idle screw on the drivers side? It also seems like once it stalls it wont restart until it cools all the way down?

 

Yes, the drivers side accelerator linkage . Hot start problems may be something different. Cold start you are on the fast idle/choke setting, if at operating temp it should run off the regular idle screw. If you can give it a little gas and it starts then I'd say it was related. Hot start problems can be vapor lock, heat boiling gas out of fuel bowls etc.

 

How can i tell if it is vapor lock or fuel boiling out and how can i fix it?

 

Lets get it to idle first. Still could have a idle circuit problem. Once rpm's are up it's running on throttle and idle circuit could have a blockage.

 

I dont think i have the throttle linkage on the drivers side right. The screw isnt even touching the lever. I have been trying to get it started today with no luck. It turns over but it wont fire up evrn with starter fluid. I will try to look at it again when it stops raining.

 

Screw it in till it touches, maybe a bit more then when fast idle kicks off it should run and you can adjust it to where you need it. This is with it cold and choke open.