82 D 150 lean burn. My EGR valve is not working. I can push pull the rod by hand so I know it is not frozen. I don't own a vacumn gage, is there any way to test the valve ? Thanks

1. Rev the warmed up engine and look for the EGR valve rod moving. If it doesn't move, then something in the vacuum hose, vacuum amplifier, etc is broken.
2. With the engine at idle, use your mouth (you might want to buy a vacuum pump/gauge at this point to avoid this) to apply suction to the hose connected to the EGR valve. If the rod doesn't move and/or the idle doesn't drop and the engine stumble, then the valve is bad.

Let us know how it worked.

Thanks Fred, should have thought of the old suck the hose technique myself, it worked easily and the valve is good. Now I need to determine why the vac amp is not providing vac to the valve. I have replaced the vac amp & EGR in the past simply because I had no idea how the vac amp works. An explanation of how this works , both electrically and vac sys would help. Is there any test proceedure for the vac amp? Thanks

Prospector,
Are the EGR vacuum hoses original? If so, then I would replace them first. I replaced mine after discovering how brittle they were. You could have a cracked hose that is difficult to notice. Same for the vacuum hoses of the other systems. I did mine all at once with rubber hose and used cable ties to make a hose bundle. It takes some care to not mix everything up.

Do you still have the vacuum hose routing label under the hood or a manual showing one? My 1987 van service manual shows several variations of EGR systems for federal, CA, or Canada specs and /6 and V8 engines. EGR solenoid, Vacuum amp, CVS5P valve, aspirator valve, etc. are used for different applications. My 1987 /6 federal spec van (not lean burn) uses an EGR solenoid (the electrical signal comes from the ESA computer and prevents EGR operation during warmup) and a vacuum amplifier. What does your engine have? What carburetor? Knowing that the hoses are good and what setup you have then I can suggest some troubleshooting tests.
Fred

Fred, the vac hoses,vac amp & EGR were replaced in '91 or '92 and all appear in good shape not brittle. The truck has 128k orig. miles, I'm the original owner.The carb is the lean burn model,4 wires & fixed adjustments.The smog diagram is like new and on the inside of the fender well. The smog & vac hoses are set up as shown.The vac amp has three hoses, one to the carb,one to the EGR & one to a solenoid? elec wired device mounted next to the vac amp. Any help determining whether the vac amp needs replacement would be appreciated.

My egr valve appeared to be working normally. But had a bad vacuum leak. The only way I could find this was to spray it with WD-40 while the engine was running. I sprayed the gasket area and the actuating rod at the base and there was a change in rpm.(vacuum leak). I don't know how long an egr valve lasts but I would replace mine every couple of years. These things are exposed to alot of engine heat and exhaust gases which cause the seat to leak and on the other end the diaphram could be leaking. I would spray your vacuum amplifier and every this else with WD-40 while the enging is running just to see if there are any vacuum leaks.Good luck !
D150ram

OK, I'm not familiar with your setup, but I'll give it a shot. The vacuum amplifier uses a strong vacuum source, the manifold, to operate the EGR valve and it is controlled by a weak vacuum source, the venturi of the carb. The venturi source is too weak to do it by itself, but it provides the signal for EGR operation at just the right time, after idle and before WOT. EGR at idle and WOT is not good. The other stuff, like the EGR solenoid, keeps the EGR off during warmup, hot restart, whatever.
1. The hose that goes directly to the carb should have manifold vacuum on it. See if it has 20 inches or so of vacuum on it at idle.
2. The hose that goes to the solenoid should have venturi vacuum on it, which is zero at idle and more off idle. My manual says that only 1 or 2 inches of vacuum will operate the vacuum amplifier. See if the hose from solenoid to carb and solenoid to vacuum amplifier are showing that venturi vacuum. If you have a pump, see if 1 or 2 inches of vacuum will get the EGR running.
3. The solenoid is closed during warmup and restart, but I am not sure if, on your setup, that means no-power, not grounded or whatever. On my 1987 the solenoid always has +12 volts on one side and the computer grounds the other side to energize it and turn off the EGR. So when the computer opens that ground, the EGR system can operate. Try bypassing the hoses to the solenoid and see if the EGR operates when you rev the warmed up engine.
Let me know if this helps.
Fred