Have a 1997 Chevy 2500 express with the 5

JOELUECK

MEMBER
1997 CHEVROLET EXPRESS
156,000 MILES

Have a 1997 chevy 2500 express with the 5.7 ltr. Thing runs fine and no check engine light is on! But I'm getting really bad MPG (9mpg). The guy I bought it from said he was getting 18 hwy. So checked the exhaust very little airflow coming out. So I replaced the muffler. More air flow was noticed it was quit a bit louder and then the check engine light came on. Code was for a mass air flow sensor, replaced that and still had the engine light on! Ended up replaceing a oxg sensor. Light went out, but still 9mpg! Called chevy garage and they said to check timming and put at 26degrees. Did that still 9mpg! Went to re-time one more time and noticed dist. Movement. Pulled it and gear on the bottom was wore out, so bought a new one and put it in and timed it to 24 degrees. Could not get 26 it would run rough! MPG went up to 11 !
could really use some imput or help, PLEASE!

1 Reply

CJ MEDEVAC

MECHANIC
11,004 POSTS

THIS MAY SOUND LIKE A CRAPPY ANSWER

WHEN SOMETHING "NEW TO US" ARRIVES............SEE MY ANSWER IN THIS LINK............THERE'S TWO LINKS IN THERE TOO!

https://www.2carpros.com/questions/1993-acura-vigor-this-great-car-now-giving-little-trouble-exhaust-leak-on-loud

(I HUNT AND PECK RATHER SLOWLY--LINKING HELPS ME A LOT!)

JUST "CATCHING UP" MAY HELP YOU A BUNCH, AND MAKE YOU FEEL BETTER ABOUT THE "CONDITION" YOU KNOW 1ST HAND THAT YOU HAVE DONE TO YOUR RIG

LET US KNOW HOW IT GOES

THE MEDIC

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