Ok guys I need your help and fast!

Please.

Ok I cut my booster line for my breaks, put a tee on it and then conneted it to my PCV.

What i did was put my PCV on the main vacume instead of the back Plemium for the PCV, i heard that a lean #8 leads to a lot of Ford 5.0 failures.


Ok I just went to drive and thought i was going to die.

Hit the breaks and i wasnt stopping, almost like someone was pushing up on my break pedal (MY power breaks are gone, now manual i think)

Also I felt my PCV and it was no sucking barely anything.

Before when i put my finer on it, it sucked it in so fast it scared me, now it feels to be about 1/10 of that.

Also my idle is super low, like around 500rpm's in drive idle.

BUT, with the idle i disconnected my battery so my ECC might be adjusting atm.

Please help on idea's

Only think i could think is the hole's inside the Tee are too small?

No leaks because i dont here any squeaks or noises.

Adam

 

I did the same thing - almost. Instead of using the booster vacuum, I tee'd into the vacuum line that comes from from
a caninster that's right next to the brake booster. It's a 3/8"
line, and I haven't had any problems at all.

you might try that...

msautry

 

The brake booster line is just for that...the brakes. Dont tap of of it or you will get the problems that you have found. I had a slight leak in my line and the prob I got was that the brake booster was applying the brakes by themselves. So you can get all sorts of different probs.

 

Well im pretty sure it was just that the hole was too small, as far as not tapping the booster line, it wont make too much of a difference in the pressure.

Why?

Your plugging the one anyway, that will "put" a negitive flow if you were to just leave it plugged (The PCV im talking about) and not cut it in any where, now when you add another unit off of another line, the vaccume wont be as much, but with in 1-2 psi from org.


Just simple physic's there.

Adam

 

Given the problems that can occur with loss of vacuum to the booster, tapping the dedicated line for it only increases the margin for error in the future. Its like stringing several extension cords together. Yeah, they may work but the likelihood of one of the connections failing (or getting pulled apart) is increased each time you add another extension. Likewise with vacuum connections.

The vacuum pressure in the manifold is uniform and both the PCV barb and the multi-barb tree in the center of the manifold are getting the same pressure. Unless I am confusing my physics, I don't see how that helps anyway. If you want to decrease vacuum pressure to the PCV, you would want the source to be restricted (i.e. smaller diameter hose), not just shared with several other components. By splitting off the brake booster line, you are asking the initial pressure in the manifold to provide enough vacuum for BOTH the brake booster AND the PCV through a line that is sized to run only one such component. If you are drinking through a straw and suddenly cut another hole in the side of it. It takes more vacuum to pull the same amount of fluid through the straw. There isn't any more vacuum to be had than the manifold pressure. Adding a "T" to ANY of the other components will effectively REDUCE the total amount of vacuum that component receives AND the component you have added to it UNLESS you resize the port AND the line accordingly. Like any other pressure-based system, it will equalize itself along the path of least resistance. Some components may not readily show any outwards signs that the reduced vacuum is a detriment (others like your brake booster will) however, rest assured that IS what is happening.

 

Well, i dont know the volume of air that could be pulled through a 3/8 (i think) hose, but I know it is more than 20 PSI.(Wrong terminoligy, maybe?)


But the tee i use was for down to a 3/16, so the hole was TINY, such as you said it decressed the vacuum.

So Grey, what would you say is the best path to take?

Thanks againm grey , you're always a big help.

Adam

 

Youngblood,

I would go for ANY vacuum source OTHER than your brake booster. You might try reducing the size of the line from the regular PCV barb at the back of the intake. A piece of 3/8 line should accept a piece of 3/16 line inside its diameter which should effective cut the vacuum in half.

The trick may have worked IF you hadn't tapped the booster line AND reduced tubing diameter. Personally though, I would go back to the regular PCV barb 'cause any possibility of compromising the brakes just gives me the *******!

 

Can you guys explain what is the reason for doing any of this to begin with. I know I have the # 8 problem on mine, not sure if anything can help it now, but seems like you are talking about something I can try.

 

Mainly, the vacuum connection Ford used for the PCV was located in such a way that it dumped into the #8 intake runner on the intake. Years of sucking up nasty crankcase gases through the PCV valve and dumping them down the #8 cylinder have been known to cause problems with that cylinder, as the bad stuff isn't equally distributed to the other seven. Don't know if this was a fluke for '85 and '86 only, but when I rebuilt my 302 I relocated the PCV vacuum line to the small tree on top of the upper intake manifold. I had a connection off of the tree that was capped off by Ford, and had good vacuum at idle. The size was slightly smaller than the 3/8" line I used.... 5/16", perhaps? Even so, a small hose clamp around the reinforced, oil resistant PCV hose I used sealed it up nicely.

 

The idea behind reducing the amount of vacuum is to reduce the overall amount of blowby that the PCV system is sucking down into the #8 cylinder.