What does it mean when you do a smoke test for a vacuum leak I did one on my 1991 foxbody LX 5.0 coupe and the only place it leaked was out of the EGR valve. What can happen ?
Engine EGR valve
- Thread starter Mindseye007
- Start date
Common spot for it to leak but it's doesn't matter. EGR channel is under positive pressure and is not part of the vacuum system of the engine. This would be filled with exhaust gas from the combustion chamber and under positive pressure.
What likely happened is the smoke from the tester made it's way to the combustion chamber that connects to the EGR port and the smoke made it's way up. You can try rotating the engine by hand to close the valve on that cylinder which, or just disregard the result. I usually pull the EGR off and put a plastic bag over the port and bolt it back when smoke testing.
I've run brand new aftermarket and NOS egr valve and they leak at the seat.
EDIT: or they leak out of the diaphragm. That's a vac leak. Cap the line to check this.
What likely happened is the smoke from the tester made it's way to the combustion chamber that connects to the EGR port and the smoke made it's way up. You can try rotating the engine by hand to close the valve on that cylinder which, or just disregard the result. I usually pull the EGR off and put a plastic bag over the port and bolt it back when smoke testing.
I've run brand new aftermarket and NOS egr valve and they leak at the seat.
EDIT: or they leak out of the diaphragm. That's a vac leak. Cap the line to check this.
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Or, the EGR could be bad. I had a new valve out of the box that was a massive vacuum leak. A smoke test identified it.
Disconnect and plug the vacuum line going to it. The re test.
Disconnect and plug the vacuum line going to it. The re test.
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is that way my car sounds like it has a Cam cuz the EGR is stuck and wont open? I have not taken it off yet to see.
this is what my car sounds like and this person unclogs the EGR on his to fix it. check it out
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