Chasing a vacuum leak on my 3.8 Montero and during a smoke test, I found smoke coming out of the EGR valve. Anyone know if these should be air tight?
View attachment IMG_2534.mov
View attachment IMG_2534.mov
3.8 EGR Valve Leak
- Thread starter tadeon
- Start date
MontySquareo
Active member
It looks like a vacuum leak to me
I did a little more research on other forums and here’s what I found:
“There’s no o-ring or internal seal where the plunger shaft passes through the body. Under normal operating conditions this EGR passageway is under positive pressure at all times. Any leak would be outwards, but it's not metered air. During the smoke test, with the engine off, the smoke travels through the vac lines into the intake and down through an open valve into the heads. The smoke will then travel up the EGR passageway to the EGR valve and eventually leak where the shaft passes through the body from the diaphragm. When the engine is running, this passageway is not under vacuum. It's under positive pressure.”
So I guess it’s technically not a vacuum leak and operates normally. Thanks
“There’s no o-ring or internal seal where the plunger shaft passes through the body. Under normal operating conditions this EGR passageway is under positive pressure at all times. Any leak would be outwards, but it's not metered air. During the smoke test, with the engine off, the smoke travels through the vac lines into the intake and down through an open valve into the heads. The smoke will then travel up the EGR passageway to the EGR valve and eventually leak where the shaft passes through the body from the diaphragm. When the engine is running, this passageway is not under vacuum. It's under positive pressure.”
So I guess it’s technically not a vacuum leak and operates normally. Thanks