I just purchased a 1995 4wd blazer with the 4.3, and was suprised with the poor fuel economy we are getting. 2 tanks later to verify my math and we are only getting 9-10 mpg a combination of city and highway driving. 177,00 miles runs great, we replaced air filter and spark plugs when we bought it just so we would know they were new. Anyone else ever come across this? Any help, or input would be appreciated, thnx

 

The '96 GMC Jimmy we just got for my daughter has been running 19-22 mpg on the highway on two 700 mile trips. Only 81,000 miles on it. Original window sticker shows a highway rating of 21 I think.

 

Sounds like a leak to me. It could not burn that much fuel and come close to running right unless you never get out of 2nd gear. Get it scanned for codes and go from there.
GL

 

thnx will have the codes read, although its a 95 and autozone cant read it even though its a 16 pin connector. I will take to local shop and have them read em for me.

 

Do you do any routine maintenance on your truck at all? I was getting 13 mpg on my 1995 Chevy S10 Blazer. For the last 2 weeks I replace thermostat, new antifreeze, new air filter, oil filter, and oil. Hope it will start to improve my engine life and fuel economy on my 4.3 Vortec. The pervious owner that I bought the Blazer from must never did nothing with it at all.

 

Mine only gets 14 and everything is new

 

Ok I will check my again after I fill up the gas tank. I need to replace these anyway so my motor can last longer. I can't believe that guy who owned it before me didn't replace nothing.

 

I only get about 15 average, i can squeeze 18-19 in the summer all highway. Winter blend fuel + idling + longer warmups = ****ty mileage.

 

The 95's do not have the best fuel injection system...the spider and popet valves. They leak alot....intake will have fuel puddles in it...just not a good system at all. And then there is that EGR valve...which will get stuck open due to a piece of carbon.

Replacing the spider assembly is not too difficult....cost is about $200; be sure to get a nut kit....and of course gaskets. Takes about 4 hours for the DYI to do it...most of which is cleaning out the burnt fuel puddles in the intake.

I finally sold my '95 and got a 2002....much better fuel management system....had 234,000 on that '95.

Good luck with yours.

 

Thnx, could the egr valve be a good place to start? My son has said that at around 50-55 mph the tach and engine surge up and down a cpl hundred rpms but below 50 and above 55 he doesnt experience that issue. when i changed the spark plugs they all were a good color and other than the above mention issue the overall driveability and start up of blazer are great.