very bad gas milesage

Asked by Jan 09, 2011 at 08:08 PM about the 2003 Chevrolet Blazer LS ZR2 4WD

Question type: Maintenance & Repair

I have owned my Blazer for almost two years and had a major tune up recently:  wires and plugs replaced w/double plat, cap & rotor, fuel and air filter.  The mechanic said that it was in real need of a tune up as he inspected the parts that were replaced.  The Blazer runs well, has good pick up & go, idles a little rough as it always had.  I thought the mpg would increase if anything, but it went from an average of 16mpg down to just over 12mpg.  The cost of gas is killing me!

2 Answers


A couple thoughts, 1. Make sure the wires are all on tight 2. disconnect the battery and let the engine computer re-learn, now that it has better airflow, etc (not sure if this applies to your vehicle, but I know it worked on my friends Grand Cherokee) 3. Run some "sea foam" through it to clean out the engine and injectors (1/2 bottle in the brake booster and 1/2 bottle in the gas tank) These are just a few things that MIGHT work. I'm definitely not a Chevy man but its some pretty general ideas


clean the throttle body it helps drimasticly

Your Answer

Add photo

Related Questions

Search Chevrolet Blazer Questions

Chevrolet Blazer Experts

#1 Andrew Olsen
Andrew Olsen
Reputation 2,010
#2 yetilikesbeer
Reputation 1,320
#3 Rowefast
Reputation 1,030
View All

Related Models For Sale

Used Chevrolet TrailBlazer
98 Great Deals out of 4,682 listings starting at $999
Used Chevrolet Tahoe
579 Great Deals out of 32,759 listings starting at $1,500
Used Chevrolet S-10
8 Great Deals out of 1,314 listings starting at $1,999
Used Chevrolet Silverado 1500
1,905 Great Deals out of 182,391 listings starting at $1,595
Used GMC Jimmy
290 listings
Used Ford Explorer
900 Great Deals out of 65,295 listings starting at $799
Used Chevrolet Colorado
242 Great Deals out of 27,197 listings starting at $1,000
Used Jeep Grand Cherokee
1,066 Great Deals out of 73,679 listings starting at $1,200
Used Ford F-150
2,138 Great Deals out of 195,050 listings starting at $290
Used Chevrolet Suburban
280 Great Deals out of 19,163 listings starting at $1,995
Used Toyota 4Runner
226 Great Deals out of 19,038 listings starting at $2,195
Used Chevrolet Camaro
348 Great Deals out of 31,304 listings starting at $2,500

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.