1998 Chevy Truck Excessive Fuel Consumption

1998 CHEVROLET TRUCK
114,000 MILES • V8 • 4WD • AUTOMATIC
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JASTAD
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Hello,

I have 1998 Chevy K2500 with a 350 V8. I just had a used motor put in the vehicle two months ago. Ever since my gas mileage has been terrible. It’s been around 11 miles per gallon. I had another mechanic look it over, and he has replaced the fuel injectors, computer, and O2 Sensors but its still reading the truck is running rich. He also tested if there was a vacuum leak but he said there wasn’t. Do you have any Ideas??

John
Jul 23, 2008 at 2:43 PM
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DOCFIXIT
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How is the compression in the used engine?
Check engine light come on?
Jul 23, 2008 at 2:54 PM
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JASTAD
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Yes the Check engine light is on. that is what is telling us the engine is running rich. and compression is good.
Jul 24, 2008 at 10:02 AM
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DOCFIXIT
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If you have a diagnostic scanner check the MAF and see what injector pulse width and does engine have a 195 temp thermostat?
Jul 24, 2008 at 3:54 PM
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JASTAD
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We actually switched out the MAF with a new one and that was not what was causing it.

How do I check Injector Pulse?
Jul 24, 2008 at 4:40 PM