87 S10 Tahoe Blazer 2.8 4wd 58,000 actual miles 2 owners first one a old lady now a old man I have been working on gas mileage for the past year changing out parts like crazy, slowly though I'm poor. I got the mileage right but not a miss and not a smooth idol. I started with it that way before changing anything so that's not making the problem. I,m not getting the miss from wires, plugs, vacuum, air,new injectors, rebuilt throttle base and regulator,throttle position censor. I'm down to pulling my hair out except I don't have any LOL. I feel the miss untill over 30 then I can't yell it anymore. I seam to still feel the roughness though like a universal joint stating to vibrate at first before getting real bad. I
know thats the motor being rough. OK I'm at changing fuel filter any suggestions
on that? OK the full filter is not where it suppose to be on my blazer under the drivers seat area under car. The only thing that looks like a filter is on the front of my engine behind a bunch of things hard to get to, will take all day to change at my speed and patients. Can a dirty full filter cause such a problem before I tackle this issue . Is this my full filter in the front anybody else with a 87 to tell me?

 

A clogged fuel filter may do it. As for the location of said filter I'm not sure. I have an '89 s10 blazer 4.3 and it's mounted under the car, driver's side. If you do manage to replace it I would recommend putting in a bottle of Gumout fuel injector cleaner. Any contaminants not captured by the filter could affect injector performance.

 

I finaly found the filter and yes dirty dirty muddy looking gas came out. I had 1/2 tank of gas left so I put in the gumout and ran it almost out and put in some Shell gas and amazing it runs great mileage back up to 18 on highway 15 in town and smooth. Thanks