So I was driving home the other night when my 4 door 95 Blazer 4.0 liter LT started to idle like crap when I stopped. It was displaying all the symptoms of a dirty EGR, hard braking, somewhat of a sulfur smell, slight hesitation when accelerating. So yesterday I pulled the EGR valve off, dumped some Seafome in it and left it overnight. Came out nice and shiny, scrubbed the carbon out of the block, put the valve back on with a nice new shiny gasket. Well it runs about 5 percent better. I dumped the rest of the Seafome in the tank and now it runs somewhat better but it still idles pretty rough. I got a tune up done last year, replaced all the spark plugs/wires, cap and new filters all around. I even opened up the butterfly valve on the TB and it's still nice and clean. I do plan on taking my truck to the part store tomorrow so I can get a reading, but in the meantime does any one have any ideas? It has 285 000 kms on it, if that helps. Oh yeah, I also hammered on the cat converter and no rattle. That's all I can really think of, I'm somewhat of a noob at this, so any help would be greatly appreciated. I just want to get it up and running before the snow flies. Oh yeah, and my heater fan went as well, any one ever replace one of those? Sorry for the long post, TIA.

 

i would try a iac or maf sensor and never hit a cat converter with a hammer the catalist brick inside is very fragile and can easily be damaged and cost you big money a smack with your hand is all you need to tell if the brick is loose inside a leek in the air inlet or inproperly seated air filter will cause them to run up and down in rpms