Ok well I have a 1995 Blazer 4.3, and it just started running real rough so the first thing I did was to attempt take the EGR valve to clean it. Well not really the easiest thing unless I'm missing something. First off the two bolts were a pain in the ***, the bottom one wasn't too bad but the top one was a sob and with a open end wrench it took FOREVER to loosen. Anyways finally did all that got it off, worked its way out and did the cleaning. Now I didn't get to do the best job of removing the old gasket on the motor its self due to being not that accessible so did the best I could. I cleaned the valve with carb cleaner did a little brush cleaning and put her back on with a new gasket. Tightened the bolts and started her up. Well I didn't have the top bolt tightened all the way because I could fill air were it wasn't sealed up all the way on the bottom. So tightened some more and still leaking air!!! Now my questions are this: Do I need to use some sort of gasket sealer when putting the gasket on, should I remove the upper plenum to get direct access to the bolts to get it tightened correctly, how do I remove the upper plenum (searched didn't really see a how to or anything), what do I do from here? When I retightened the upper bolt I was using a 10mm open end wrench since my 3/8 drive ratchet would fit right, mabye if I had a wobble it would of been better, anyways I had a breaker bar on it and it was tight as hell so not sure what the hell is going on. Just for a quick second a did test drive it the other day and noticed a hell of an improvement, however today when I ran to the store it stalled out on me on the first turn, now I'm assuming this is due to the vacuum leak, so sorry for the long post but any ideas, suggestions or threads will be very helpful. Thank you for your time.

 

TTT.....Please Anyone?

 

Wish I could help, but yours sounds different than mine. I have a 93, the bolts on mine is at 9 & 3 oclock.

 

I'm assuming the Check Engine light being on is why you took the EGR valve off. What DTC was in memory? If there's a problem with the valve, the light will come on. All of the old gasket must be removed for the EGR valve to seal properly. Don't use any type of sealer, just the gasket.

Have you checked fuel pressure and leakdown? Low fuel pressure or excessive leakdown can/will cause the rough running you're experiencing, and there's a good chance the check engine light would NOT come on.

 

Hmmm....that's the thing there was no light, however I went off of went this "mechanic" said. He said that the valve could still be stuck open with carbon build up and it wouldn't trip the light. I wanted to raise the b.s. flag on it but I decided to give it a shot.
Fuel pressure, to be honest I'm not sure how to even check that or even have a gauge to check. I could run up to harbor freight and probably find a cheap one there. Any help on checking the pressure? Ya, I have no idea what leakdown is lol. Now I will tell you this, now there is like NO power what so ever. I hit the pedal it hesitates and barely goes.

 

There may be something else causing the problem but, with the symptoms you're having, this would be a likely place to start looking for a problem.

Back by the distributor, on the driver side, there is a service port in the fuel pressure line. You'll need to connect a fuel pressure tester to that port. Key ON, Engine OFF, fuel pump running: pressure must be 55psi to 61psi, and it must remain above 50psi for 10 minutes after the pump shuts off. Post your results.

 

I have been experiencing the same problem on my 95. I did a pretty good cleaning on the EGR valve and reinstalled it (dont worry I had trouble with the uninstall and install too, tight place). I had the ses light on before, and this fixed it. It helped with the engine not running as rough, but I also put in some fuel treatment/injector cleaner too. Are you experiencing any soot coming from the exhaust? Or a rough idle? Those are my problems as well. Getting the EGR valve seated is a pain, but take some patience and a swivel extension wrench and that should help. Anyone have any fix-its on my similar problems?

PS were able to get a reading on a scanning tool? I havent had anyone able to get any reading besides an error....?

 

The best advise I can give you is to get a big valve wrench and beat the heck out of it. If nothing else you'll feel better.
Cheers