EGR and EVR vacuum tubes
 

I noticed on my son's 96 ranger, the EGR is plugged, and one of the EVR ports are broken off and neither is hooked up. Also, the vacuum lines are completely missing. Can I simply use vacuum hose to hook this back up? Is there anywhere one can buy the green and red vacuum lines?

Also, I know the port on the top of the EVR goes to manifold vacuum, and the other goes to the EGR. Could someone point me to where the manifold vacuum port is on the manifold for the EVR?

Wrecking yard is the only place you are likely to find the colored hard plastic vacuum lines, these are cheaper than the rubber lines which is why car makers use then, they are colored for easier assembly/hookup at the factory.

You can use any type of vacuum lines to replace them

EVR(EGR solenoid) will usually be hooked to the Vacuum Reservoir line, so it has vacuum available all the time
Vacuum reservoir has just two lines so EVR line will be "T'ed" to one of those

Vacuum reservoir is a black plastic ball usually located on passenger side front of engine bay, very low down, you often can't see it from the top, have to get under front to see it

There will be a vacuum line coming from upper intake running to the reservoir, it will have a Check Valve on that line that holds vacuum in the reservoir, the EVR "T" will usually be between Check Valve and Reservoir

Ok, great! This is exactly what I needed. Maybe this is why my heater selector isn't working either. Could be leaking vacuum where things aren't hooked up correctly. I'm thinking someone broke off the top port of the EVR and instead of replacing the EVR just blocked off the EGR valve. Any idea what size the vacuum hoses are? If not I can figure it out when I buy the new EVR.

I'll report back when I get things figured out.

Yes, the Vent controls, floor, panel, defrost, are vacuum controlled, defrost vent is default/no vacuum

There is a black plastic vacuum line that runs from vacuum reservoir to the firewall, passenger side next to heater fan motor box, that line supplies vacuum for the Vents, and yes if EVR connection was left open then you could lose vacuum at Vents when accelerating, low vacuum in intake manifold

But the black plastic line would also melt or crack near the exhaust, causing same loss of vacuum in the cab

No, on the size, just take old EVR off and match its size
Also if you have the old plastic line take that in as well and get a short length of rubber hose to have on hand to splice any breaks in these lines, it just needs a snug fit, no clamps needed, as its Vacuum pressure so pulls on splices/connections, it doesn't push them apart

Ok, thanks for the advice. It appears someone has taken the vacuum line completely off and tossed it...I don't see it anyway. But, I'll look again. I'll probably buy several feet of vacuum line and just replace them.

EGR system also has a DPFE sensor with 2 hoses, they are not vacuum hoses, they are exhaust hoses, they connect on the EGR valve tube
DPFE sensor tells computer how far open the EGR valve is, how much exhaust is being added to intake
It does this by the pressure difference between these two hoses, hose closer to EGR valve will be same pressure as farther hose when EGR valve is closed, as EGR valve opens the closer hoses pressure will go down, the difference in pressure tells computer the "flow"
DPFE = Differential pressure feedback

Should be hooked to the Vacuum manifold, multiple vacuum ports at one location on the intake manifold, follow Power brake vacuum hose, it should also be plugged in there.
Follow each vacuum line that's already hooked up, you should find one with a "T" that unhooked

Also look on the rad support, there should be a vacuum diagram there

Blend door is Electric on 1995 and up Rangers, it was cable operated in 1994 and earlier
Vent doors have always been vacuum operated

Update: The only port I could find was a port on the intake on the drivers side, so I routed a vacuum line from the vacuum reservoir to that port and got the heater controls working again. I have no idea if it has the EGR operating correctly however. I do know the EGR valve works because when I pull the EGR vacuum line and put suction on it, the engine RPM decreases and almost quits. My question is, when I pull the vacuum hose off the EVR (the one that runs to the black plastic vacuum reservoir) I don't feel any vacuum on that line (I know the reservoir is working because the heater controls work now and did not before), but I'm not sure I would since the line is so small and it's coming from the reservoir. Should I be able to feel some vacuum there?

EVR should have vacuum available from the vacuum reservoir, if thats where its hooked up, on ONE of its hoses, the vacuum hose on the EVR going to the EGR valve would have no vacuum until you were driving and engine was under a load, thats the only time EGR system is used

Yes, it should have vacuum

There are only 2 ports on a Vacuum reservoir(some only have one)
One is for source(intake manifold)
The other is Load(devices, like cab and EVR)

Some vacuum reservoirs have built in Check Valve, others don't and have a Check Valve on the Source line

Check valve looks like this: https://images-na.ssl-images-amazon....1KV04JZS2L.jpg

You can only blow thru it in one direction
If vacuum reservoir has built in check valve then same thing

So test if you have a working check valve
Start engine, select defrost in cab, then shut engine off
Select Floor now, you should hear the vacuum motor move the vent door closed, if not you have no vacuum in reserve, so no vacuum with engine off
If you hear vent door change then you have vacuum reserve

Power brakes use a check valve, you can do the same test, shut engine off and press brake pedal a few times, you should get 2 or 3 presses with power assist, then vacuum will be gone and pedal will get hard to press, this reserve is in case engine stalls while driving, allows you to stop the vehicle safely




'

Ok, thanks. I'll test that this weekend. I don't recall seeing an in-line check valve (since the PO removed the vacuum line completely) so if there is not one built in the reserve, should I add one in-line? Will the constant vacuum collapse the reservoir if it doesn't have a check valve?

You can add in-line check valve regardless, then add a T for the EVR between check valve and reservoir

Ok. On my reservoir (have to forgive me...the PO removed all the vacuum lines except the plastic line that goes from the reservoir to the EVR), there is a port in the front that was plugged off with a rubber plug. That's what I removed and ran manifold vacuum to. On the back of the reservoir, I believe there are two ports....one has a factory hard plastic line that appears to run to the EVR (when the PO broke the nipple off the EVR, they plugged the vacuum line from the reservoir to the bolt sticking out of the fender well holding the coolant bottle on...) and the other plastic vacuum line runs to the cab for the heater selector. If I recall correctly, I tried sucking on the line that comes from the reservoir to the EVR (from the EVR side obviously) to make sure it wasn't blocked, and I could only get air to flow one way. So maybe there is a built in valve there. I don't know.

If not, should I simply add a check valve to the line that's coming from the front of the reservoir to the intake, or should I plug that back off. And if so, how should the vacuum hoses be plumbed exactly? '

Sorry to sound like such a dunce on this but I want to put it back correctly as this is my son's truck and not only do I want it right, I want him to learn the right way.

The intake SUCKS air from the hose and vacuum reservoir
So if it has a built-in check valve on that one port, you could BLOW into the other two ports but NOT suck air from the other two ports

So if you can blow into the EVR hose but NOT suck air out, then that port should be OK for EVR or Cab

For the hose that's on the intake you should be able to Suck air out(with one of the other hoses unhooked), but NOT blow air in, so opposite of the other two ports
If so then that port has a check valve built-in

Yes that makes complete sense, and I believe that's how it was...I could blow air into the EVR hose going into the reservoir, but I could not suck air back out. That's why I thought I'd feel vacuum on that line when I pulled it off the EVR but it sure didn't seem like I could feel it. I'll check both sides and report back.

Do you think the way I have it set up is correct (front hose vacuum from intake, back two lines with one going to EVR, the other to cab)?

Never seen a vacuum reservoir with 3 ports so can't say.

Most have 2, and a few had just 1

It should have vacuum with engine running, after engine is off once you pull off the hose vacuum would be gone instantly

Right, that makes sense. Ok, thank you for you help! I've learned alot about how the system works so that's great! I'll report back.

Weak Accuator
 

I lose Max A/C to Defrost.

This accuator seems weak.

Would that mean this need to be replaced?

I've replaced Vacuum Ball, and a few hoses trying to trace this down.

Currently I have Permanent Max A/C lol.

Any help would be appreciated.

https://cimg8.ibsrv.net/gimg/www.ran...b9594329de.jpg

That looks like the Fresh air vent control, so no doesn't control defrost, panel, or floor directions

Diagram here: https://ww2-secure.justanswer.com/up...rer_vacuum.jpg

There are two doors that control air direction
The floor/panel door
The Panel/defrost door

They are labelled for direction and vacuum, V = vacuum, NV = no vacuum, PV = partial vacuum
So when there is No Vacuum at both doors, Defrost is the direction air will flow

Air re-circulation door is at the right, thats the fresh air door
In MAX AC this would have Vacuum, so would pull air from inside the cab to be cooled instead of hot air from outside, this is what "MAX AC" means, AC itself only has 2 settings, ON or OFF, lol
MAX AC in later years also shuts off heater core coolant circulation, the valve high lighted in yellow in the diagram

I only default to Defrost when I am on Max A/C so, that's why I'm super confused and trying to trace THOSE vacuum lines.

Does that make sense? Any ideas?

Check Grey vacuum hose in engine bay, it runs from firewall to the heater hose by pass valve, has 4 coolant hoses and a vacuum valve
It shows it as White in the diagram, but its Grey on Rangers

If grey vacuum line is broken or not holding vacuum you would get what you have

Is it possible that heater hose bypass valve is bad?