Egr?
 

Hey ive got a 95 blazer with 225000 miles on it. Runs great just finished flushing tranny and replacing filter new plugs plug wires and I ran an injection cleaning. One week goes by and suddenly it loses power at highway speed get home its lugging. When I crank it it idles up to about 2000 and when braking at a light the pedal gets really hard and it wont stop. I checked the egr and when I cleaned it and pushed the plunger the plastic just broke right out. Could the egr be causing all of these problems or maybe the booster? Any help would be greatly appreciated.

Replace the EGR that broke and throw a vacuum gauge on direct manifold vacuum. You should, at idle, have right around 20 inches. If it's lower, you've got a leak.

If it does show lower, then turn the motor off, unplug the booster hose, and plug it. Try it again.

Yes, it could be the EGR, the booster, and if you have CPI, the spider injector (are you running rich?)

The trick's to figure out what it is.

Now, if all these check out, go get yourself a propane or butane torch about 4' of hose that will fit on the end. Start the truck, and turn the gas on. Take the hose around, and when the idle changes, you've found your vacuum leak.

Don't forget though, that could have also been the computer using the IAC to compensate for something or other...

But check the simple stuff first.

I'm about ready to fall over in bed; I'll check back tomorrow and see how you're doin'.

Josh <><

Shes all fixed up! Thanks for the help man I havent been able to get on here all week. New egr and idle air control valve was bad as well. Shes runnin good again now. Thanks again