95 Quest EGR valve cleaning

[medusa]

I took EGR valve off of intake manifold to clean it because of failing emissions for high NOx and tried cleaning the hole going in to the intake manifold from EGR mounting side. A lot of black stuff came out, my question is should there be a hole passing through in to the intake manifold? I tried to stick a wire through it assuming it would pass in to the intake but was not able to pass a thin wire ( about 1/16 inch in dia ). I guess there is a temperature sensor of something mounted to the bottom of this hole/port, does this sensor block the wire from going through? How big of a hole is suppose to be going through? I tried spraying carb cleaner from EGR mounting side hoping to see it spraying in to the intake manifold but nothing passes through. Please explain. Thanks for your help.

[medusa]

I took EGR valve off of intake manifold to clean it because of failing emissions for high NOx and tried cleaning the hole going in to the intake manifold from EGR mounting side. A lot of black stuff came out, my question is should there be a hole passing through in to the intake manifold? I tried to stick a wire through it assuming it would pass in to the intake but was not able to pass a thin wire ( about 1/16 inch in dia ). I guess there is a temperature sensor of something mounted to the bottom of this hole/port, does this sensor block the wire from going through? How big of a hole is suppose to be going through? I tried spraying carb cleaner from EGR mounting side hoping to see it spraying in to the intake manifold but nothing passes through. Please explain. Thanks for your help.Wes

[medusa]

Forgot to mention that it is a 95 Nissan Quest

[Defiant]

EGRs are just vacuum-actuated valves. The garbage that accumulates in them is about half-again as strong as the mortal holding up the Coliseum. In this situation, use the Good Mechanic's Byword: It Ain't Gonna Get Any More Broke.Try chiseling it out with a worn-out screwdriver. Usually, once you get it started, it gets easier to crumble.Keep in mind the rest of the passages and/or tubing leading up to and away from the valve are likely to be similarly encrusted. Stay patient. Do not let any of it get into the intakes and into the cylinders- shop vac.

[Q45tech]

We make little EGR roto rooter from discarded pieces of throttle cable........use variable speed drill to spin the inside wire.

BG makes excellant spray throttle body cleaner which with the rooter and a complete set of dental picks and tools works well.

A small dremel tool with a flex drive works.

The hot vapor from exhaust condenses the carbon and byproducts into almost concrete.......................why you should clean EGR every 30k and it never gets blocked.

EGR along with emissions is important to steady cruise MPG. Blocked EGR can reduce your highway MPG by 4-7% depending on engine.

[Defiant]

We make little EGR roto rooter from discarded pieces of throttle cable........use variable speed drill to spin the inside wire.

"Hey, lookit that over there!" he yelled, and whilst distracted, Q45tech's clever innovation, although probably borrowed from somewhere else, was deftly stolen.