Egr Valve Temporarily Stuck Open

[crouchleyke]

My EGR valve stuck in the open position during extended highway driving (interstate). (1993 S-10 blazer 4.3 CPI, VIN W) Of course it ran bad at idle but I shut it down for the night and restarted it the next day. On the second start the valve closed and seemed to resume normal operation. This is the all electric valve and it appears to be well nested into the intake manifold. My Haynes manual says to remove the plenum to service the valve. I think it might be easier to remove the A/C to get to it. Anyone with any experience here????????? Should I remove the valve for cleaning or just nurse it along????? Is it possible to remove the valve with the A/C and plenum on?????

[GMMerlin]

Yours is not an uncommon problem..
What is happening is small pieces of carbon are breaking off from inside the EGR passage an are getting lodged in the pintle of the EGR valve.
There was a company that made a screened gasket that would prevent the pieces from entering the valve... www.tomco.com I believe they may have gone out of business.

To remove the valve, you don't need to do more than, remove the rubber air duct to the plenum, unplug the connector and remove the 2 10mm bolts that hold the valve on.
You can twist the valve so it will come out.

[crouchleyke]

OK-great information above but the next question is....is this an isolated case or can I count on more problems??? Should the valve be cleaned or replaced????

[blazerfromhell]

Originally Posted by crouchleyke

My EGR valve stuck in the open position during extended highway driving (interstate). (1993 S-10 blazer 4.3 CPI, VIN W) Of course it ran bad at idle but I shut it down for the night and restarted it the next day. On the second start the valve closed and seemed to resume normal operation. This is the all electric valve and it appears to be well nested into the intake manifold. My Haynes manual says to remove the plenum to service the valve. I think it might be easier to remove the A/C to get to it. Anyone with any experience here????????? Should I remove the valve for cleaning or just nurse it along????? Is it possible to remove the valve with the A/C and plenum on?????

Its a piece of cake to take out. No need to remove Ac bracket. I just did it last week . Froze my ass off but it takes about 20 min. Clean and test . If you have an ohm meter it easy. there should be 5 pins. Outer pins are the coil , inner pins are a coil with center tap. Should be if i am not mistaken 4-5 ohms that varie as you push the plunger in and out. Good luck