egr testing 88 4.0 cherokee

[caddy94]

how do I test my egr valve to see if it is working properly I dont seem to be getting any vacuum to it ,I realize that it shouldnt be there at all times thks

[Ironic]

There is no "bench test" for an egr valve. You can check to see if the egr passages are clear in the intake. At idle, pull the egr valve stem up- engine should stumble or even stall, if it don't your passages need to be cleaned. Best indication to see if the egr is working is to rev the engine to about 1500 r.p.m. with the engine at operating temp and see if the egr valve stem pulls back.

[Saudade]

Check out:

http://www.lunghd.com/Tech_Articles/...iagnostics.htm

[caddy94]

actually i beleive the problems lies in the egr solinoid valve always seems to be energized so no vacuum is going to the egr which is controlled be the ecu and there is where I am lost any help would be great

[89ltd]

start the engine , while idling connect a constant vacum supply to the egr valve itself, not the vacum amplifier in from of it, if the valve is working the engine will stumble or die. Not sure if you can buy the vacum amplifier seperate from the valve , i think they come together.