1982 Bronco XLT

[ArdWrknTrk]

Sounds like you are making good progress.

But, it doesn't take much of a leak to raise the idle. A cracked vacuum line, or one that is off, or even a bad power brake booster can do it. So if you put a tach on it and find that it is idling too high pull all the vacuum lines and plug the ports and see what happens.

Beyond the "controlled leak" of the PCV check valve.

If you have the throttle stop backed off to where you can see daylight and the idle still won't come down you have a leak somewhere.

It might be into the valley, with no external leaks.

Maybe pull the vent on the left side and hold a rag over the filler.

Will it throttle down then?

[Bruce moose4x4]

Beyond the "controlled leak" of the PCV check valve.

If you have the throttle stop backed off to where you can see daylight and the idle still won't come down you have a leak somewhere.

It might be into the valley, with no external leaks.

Maybe pull the vent on the left side and hold a rag over the filler.

Will it throttle down then?

Could it possibly be the idle screw on the fast idle cam not adjusted properly? Never messed with an Edelbrock carb.

[Weberman]

Could it possibly be the idle screw on the fast idle cam not adjusted properly? Never messed with an Edelbrock carb.

I open the choke all the way and make sure that the fast idle cam isn't on it either. I'll have to plug everything and see. I heard about the booster before so I pinched the line really quick and nothing happened. The other vacuum line goes to the one on the firewall which goes down to the trans and HVAC. I took the PCV valve off too to see. Question about that. I have smoke still coming out of the breather when its running. The valve is new. Is it supposed to do that at idle? Also would that indicate no vacuum leak under there since it would probably suck in and not let the smoke come out?

[ArdWrknTrk]

I open the choke all the way and make sure that the fast idle cam isn't on it either. I'll have to plug everything and see. I heard about the booster before so I pinched the line really quick and nothing happened. The other vacuum line goes to the one on the firewall which goes down to the trans and HVAC. I took the PCV valve off too to see. Question about that. I have smoke still coming out of the breather when its running. The valve is new. Is it supposed to do that at idle? Also would that indicate no vacuum leak under there since it would probably suck in and not let the smoke come out?

The PCV is there for a few reasons:

To remove condensation that naturally occurs in the engine (as the oil reaches 212F/100C) water is driven off as steam.

To remove oil smoke from contacting sources like piston bottoms and the heated crossover in the intake manifold.

To remove pressure caused by ring blow by. If the crankcase becomes pressurised it will start pushing oil past the gaskets and seals.

All this is to say allowing 'smoke' to escape is its purpose.

But again, you can have an internal vacuum leak and never find it.

I would check ALL other options before pulling the intake.

If you had a Holley I might suggest the secondaries are open too much, and THAT adjustment screw is underneath the carb.

In which case I would have suggested stuffing the secondaries with a rag and seeing if it changes things.

[Weberman]

The PCV is there for a few reasons:

To remove condensation that naturally occurs in the engine (as the oil reaches 212F/100C) water is driven off as steam.

To remove oil smoke from contacting sources like piston bottoms and the heated crossover in the intake manifold.

To remove pressure caused by ring blow by. If the crankcase becomes pressurised it will start pushing oil past the gaskets and seals.

All this is to say allowing 'smoke' to escape is its purpose.

But again, you can have an internal vacuum leak and never find it.

I would check ALL other options before pulling the intake.

If you had a Holley I might suggest the secondaries are open too much, and THAT adjustment screw is underneath the carb.

In which case I would have suggested stuffing the secondaries with a rag and seeing if it changes things.

I hope it isn't internal. I wouldn't think it would be since it was before and after I had the intake off to take the head off so thats two different times by two different people. I'm basically looking at the other vacuum line now hopefully.

[Weberman]

I hope it isn't internal. I wouldn't think it would be since it was before and after I had the intake off to take the head off so thats two different times by two different people. I'm basically looking at the other vacuum line now hopefully.

Went up to the junkyard and got the extension and sender. Its at the O on normal on warm idle so, whatever psi that is haha.

As of the idle still not sure. I put a vice clamp on the PCV valve and it seemed to idle lower when hot. Still space inbetween but its low. I took off the HVAC hose and it was sucking pretty good and put my finger on it and there wasnt a change. Took the vacuum manifold supply hose off and put my finger on it and there wasn't a change, so I guess the trans and HVAC isn't a leak. Would a valve cover gasket be a vacuum leak since the PCV is on it? I say that because the gaskets I had were not that good and leaked everywhere and I've had to keep tightening them. They still leak some but the tops could be letting some in for all I know and wouldn't show a leak.

[ArdWrknTrk]

Went up to the junkyard and got the extension and sender. Its at the O on normal on warm idle so, whatever psi that is haha.

As of the idle still not sure. I put a vice clamp on the PCV valve and it seemed to idle lower when hot. Still space inbetween but its low. I took off the HVAC hose and it was sucking pretty good and put my finger on it and there wasnt a change. Took the vacuum manifold supply hose off and put my finger on it and there wasn't a change, so I guess the trans and HVAC isn't a leak. Would a valve cover gasket be a vacuum leak since the PCV is on it? I say that because the gaskets I had were not that good and leaked everywhere and I've had to keep tightening them. They still leak some but the tops could be letting some in for all I know and wouldn't show a leak.

The PCV is a "calibrated" leak, that is always there (and accounted for)

You could pull the valve right out of the grommet and it shouldn't change a thing.

But your engine will probably start leaking and getting gunked up more, and it won't be as good at boiling off condensation.

[Weberman]

Went up to the junkyard and got the extension and sender. Its at the O on normal on warm idle so, whatever psi that is haha.

As of the idle still not sure. I put a vice clamp on the PCV valve and it seemed to idle lower when hot. Still space inbetween but its low. I took off the HVAC hose and it was sucking pretty good and put my finger on it and there wasnt a change. Took the vacuum manifold supply hose off and put my finger on it and there wasn't a change, so I guess the trans and HVAC isn't a leak. Would a valve cover gasket be a vacuum leak since the PCV is on it? I say that because the gaskets I had were not that good and leaked everywhere and I've had to keep tightening them. They still leak some but the tops could be letting some in for all I know and wouldn't show a leak.

I messed with the fuel screws and got it to idle lower and then could use the idle screw. The vacuum was pretty low and then I adjusted it back to the highest vacuum, which was about 3 turns out. Still not touching the idle screw, but seems to be idling lower after it sat over night with me messing with it. Took it out on the county road and in then higher rpms, it just falls right on its face. Also idles low enough in gear while driving after on the pedal for a bit, that it tries/does die when getting off the throttle at low speeds like turning. So too high/too low.

[Gary Lewis]

I messed with the fuel screws and got it to idle lower and then could use the idle screw. The vacuum was pretty low and then I adjusted it back to the highest vacuum, which was about 3 turns out. Still not touching the idle screw, but seems to be idling lower after it sat over night with me messing with it. Took it out on the county road and in then higher rpms, it just falls right on its face. Also idles low enough in gear while driving after on the pedal for a bit, that it tries/does die when getting off the throttle at low speeds like turning. So too high/too low.

It still looks like you have a vacuum leak.

But lets talk vacuum advance. Where do you have it connected - manifold or ported vacuum? I'm guessing manifold from what you said. So I suggest you move it to ported vacuum, meaning that you won't have vacuum to the advance at idle.

The issue is that with manifold vacuum, meaning that you have vacuum at idle, you have so much advance that it is hard to get it to idle down. But if you do get it to idle down when you drop it in gear the vacuum goes away and the idle is much lower. Way too low.

Give ported vacuum a try. I don't see in your sig what carb you have so I can't tell you where ported vacuum might be. But usually there's one vacuum connection that has no vacuum at idle and it comes in just off idle. Try that one.

[Weberman]

It still looks like you have a vacuum leak.

But lets talk vacuum advance. Where do you have it connected - manifold or ported vacuum? I'm guessing manifold from what you said. So I suggest you move it to ported vacuum, meaning that you won't have vacuum to the advance at idle.

The issue is that with manifold vacuum, meaning that you have vacuum at idle, you have so much advance that it is hard to get it to idle down. But if you do get it to idle down when you drop it in gear the vacuum goes away and the idle is much lower. Way too low.

Give ported vacuum a try. I don't see in your sig what carb you have so I can't tell you where ported vacuum might be. But usually there's one vacuum connection that has no vacuum at idle and it comes in just off idle. Try that one.

The advance is on ported vacuum. Timing is around 10-11*