1998 Chevy S-10 Gas mileage horrific

DWINEINGER

MEMBER
1998 CHEVROLET S-10

Engine Performance problem
1998 Chevy S-10 6 cyl Two Wheel Drive Automatic

After a late night tired change to the air filter, the gas mileage on my S10 has gone down insanely. (It seems like a semi gets better gas mileage). The only bit I can think about is that I thought atm was that I was thinking it was an older car with the air filter on the carb, and not a throttle body. So I'm trying to figure out what could possibly have caused the gas mileage to plummet.

3 Replies

BLACKOP555

MECHANIC
10,371 POSTS

What did u do? And how much did the gas mileage drop.

Im not understanding what your trying to say.

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Saturday, March 21st, 2009 AT 11:02 PM

DWINEINGER

MEMBER
2 POSTS

Some time ago I needed to change the air filter on my 1998 Chevy S10. With the late hour and being in somewhat of a rush I inadvertently removed the cover of the throttle body as this is where the air filter would be on my 1993 Chevy 1500 - center of engine compartment with the carberator. Unfortunately this is not where the air filter is located on the 98 S10. When I realized the error I immediately replaced the cover and removed the correct cover on the air filter in the lower right-hand corner of the engine compartment. Afterwards an intermittent high-pitched whistle developed and the gas mileage dropped. The usually 18 to 20 mpg became something more like 12-15 or, perhaps, less. It cost so much to drive that I have parked it until I can locate the cause. It seems as though I may have somehow created a vacuum leak. I had thought it may have resulted from a broken or warped seal but have been told the throttle body has not seal or gasket.