I have a 1982 f150 4x4 with a 300 i6 there are two vacum lines running to the top of the air intake thing on top of the carb i pulled them off the other day and was cleaning my carb and went to put them back on and when i put one of tehm back my truck started idiling really low and died after a minute i pulled it back off and the truck idled and ran fine before when i had them both on it would idle low sow i had to give it gas the hose is push air out if any one could help or have any ideas they would be greatly appreciated

thanks

 

Could you clerify your questions and comments a little better? It should have one vacuum line running from your vacuum source on your intake to the top lid of the air cleaner and one running from the top lid of the air cleaner to the air horn flapper vacuum port that allows cold air into the air cleaner. If you have the vacuum hose unhooked, it will speed your engine up a slight amount. It should also have a delay valve in the second vacuum line. It is directional. If it is not reinstalled the right direction, it will not allow the flapper to open. I don`t have an 82 manual to help you out. If someone has an 82 engine manual, it should show how it is all hooked up in it. Do you have anything obstructing the air coming into your air cleaner? What did you clean your carb with? Are you saying the vacuum line is blowing air through it? I don`t see how that is possible. Give us a little more info.

 

I had the same experience. There is a line that goes from the top og the air cleaner to a two pronged "manifold" on the left hand side of the engine (when looking in from the front). I accidently disconnected the line when removing the air cleaner cover and noticed a drastic improvement. My mechanic told me that my egr was bad some time ago, and I haven't replaced it yet. I was wondering if the two were related, and also was wondering if it would hurt anything to leave the beforementioned hose detached. I hooked it back up just in case....

 

i have left mine unhooked since i discovered it runs much better and it doesn't seem to have any problems it has been about a month or so now

 

I replaced my egr today, and the idle smoothed right out. I guess the two were somehow related.

 

If tuned properly, an engine will not run better with a vacume leak, although it may idle faster. If overall performance is increased with that line off, then the carb is not working properly.

 

Your vacuum lines need to be hooked back up properly for your air horn on your air cleaner to allow the proper amount of air in. If it is running better with the vacuum line open then I would say that you are starving the engine for air when you have it hooked up (air cleaner flappers). Serving_time is correct. If you are running better with a vacuum leak, you definitely have other problems somewhere else. With vacuum leaks, your fuel economy and performance will also suffer, unless, of course, you are starving it for air to begin with. I have an 82 engine manual on order. I will check how it is hooked up when I get it. You still haven`t answered all of the previous questions.

 

i cleaned my carb with bardhal carb cleaner and i do not have anything obsructing air flow the two lines are on a small bracket and one is sucking air and one seems to be push air into the filter

 

There is a part on top of the air cleaner that has two studs that insert into the forementioned hoses. The part itself sits inside the air cleaner cover and the studs protrude out of the lid. Is this the flapper that you are talking about? I did replace my egr valve and it now idles faster and smoother, which is the same effect that taking that hose off had. I also replaced the pcv valve and the crankcase air filter. Are any of these parts related to those two hoses, or is it just coincidence? Is this a part that is readily available?

 

The part you are referring to in the lid acts sort of like a choke coil. It is a temperature sensor. Your vacuum from your intake hooks to this. Your other vacuum line going to the rectangular funnel looking part (air horn)of your air cleaner assembly hooks to the other port on the coil and the other end hooks to a vacuum motor for the flapper. When the engine is cold, the sensor sends a vacuum signal to the vacuum motor that operates the duct valve (flapper). As the engine warms up, heated air enters the air cleaner from the shrouding around your exhaust manifold and warms the sensor. The sensor then limits the amount of vacuum it sends to the vacuum motor. When that happens, you get only cold air through the air horn. Look into the end of your air horn. See if you see one or two flappers. See if they are open when engine is not running and then see if they are open when engine is running and warm. You may be able to plug your vacuum line going to the sensor and everything should stay open. If you don`t have the funnel on your air cleaner, plug the vacuum line at the source. Hope this helps.

 

That all makes sense now. I will check all of that tomorrow. Everything did improve when I changed my EGR, but the cold air system might deserve a look.

 

on the little flapper where the hoses hookup one of them does not go threw it has just a stud on the top and on the back nothing just flat piece of metal