Well, after filling up today and plugging into my mileage chart I keep, I went from 16.5 mpg back up to 19.1 mpg, just around where it was before I started having problems...
Now I'm wondering if I should find the time to take my EGR valve off and see if it's all carboned up and clean it if needed to complete the tune-up...
Do they get bad on these? I know on my S-10 (a 1992) they were known to get a pretty good carbon buildup in them, but my Blazer's is a different style it appears... and MUCH more expensive...

 

glad to hear your mileage has gone up. as for the EGR, you're not going to replace it, are you? you mentioned removing it to clean it out, but then you mention how expensive it is, like you were gonna replace it.

 

How is your fuel filter?
replaced it anytime recently?

I had a cat go out once, and it got so hot coming up a hill it was making a ton of noise and glowing.
I had a fuel filter get plugged up on a motorhome (freaking hidden fuel filter) and it lost all power, and you had to be carefull on how far you pushed the pedal in or it would start bogging down spitting and spurting.
Cat had almost the same effect, but the cat was pretty obvious.

I had my cat checked out by a muffler shop, they drilled a few holes before and after the pre cat and they checked the flow that way using a torch.

 

No, maybe I should have worded that better. If my EGR Valve wasn't so expensive I'd consider going ahead and changing it, as it is quite expensive (to me) I'll just try to clean it if I can get it off and check for buildup in it.
As for the fuel filter, no clue. I haven't gotten a Haynes manual for it yet (shame on me), so not sure where it is, please tell me it's not stuck inside a framerail like on my S-10... I actually had to bribe my little sister to give me a hand on that one because my fingers were too fat to get the filter put back in and the bracket bolt started...
But that is a though because the Blazer has a tendency to start hard quite a bit, have to try to start it twice a lot...
Guess it's something else I'd better check.

 

they're all the same underneath, doesn't matter if the Dime is a p/u or a SUV. these aren't bad (i have large hands myself), try doing it on any '90's GM car, i swear they used my 6 yr old daughter's hands to design the space, it's so frigin' tight.

 

I found it, doesn't seem bad at all, on my S-10 it was actually IN the C-Frame channel, but my Blazer has solid box frame channel, so it's on the outside of the frame, MUCH easier. Come payday I think that's my next little project, fuel filter, air filter, good to go.

 

I have a 99 and its kinda got the same problem could it really be the cat? I got mine checked and they said it was good. But I know gibbles said something about it makeing noise? But when I start mine I hear aloud rattle and when I start driveing it gos away but when I stop it rattles and makes a werid kinda sound.

Mabe my cats bad?

 

brother, if your cat is rattling, then it's toast.

 

haha Yea I had a fealing that it was. Cuz i dont know many trucks or cars that rattle.

 

my cat rattles, but it's the heatsheild.

It's pretty bad, but it makes kinda a pinging sound.
I had a heck of a time trying to find the rattle, one day it was doing it while idling so I got under there and took the heatshield off and found it.