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01-24-2012, 01:22 PM #1
Very Poor Fuel Mileage on 2003 Silverado
I have a 2003 Silverado 1500 4.8L.
Over the last week or so, I've gone from around 14MPG Average to 2-3MPG Average!
Exhaust smells strong of gasoline. Poor Power.
What are the first things I need to start checking? Injector stuck open? Not sure.
Thanks!Current Daily Driver:
2003 Chevrolet Silverado 1500 - 4WD - 4.8L V8 - True Dual Exhaust Setup, Cat Delete, Cherry Bomb Glass Packs
01-24-2012, 01:41 PM #2
01-24-2012, 02:59 PM #3
The first thing I did was scan it. Not throwing up any codes. Nothing done lately. Oil Change about 1 - 1 1/2 months ago. I even verified the MPG on a secondary device plugged into my OBD. Shows the same.
01-24-2012, 03:27 PM #4
01-26-2012, 09:58 AM #5
i am surprised the truck will even run, as it would seem apperant that it is running extremely rich. thus I am suprised the plugs are even able to fire as the cylinder must be getting way to much fuel to burn off thus the strong smell of gas. Fuel injectors could be malfunctioning or are jus flowing fuel instead of spraying it as they should. And to not have a code seems weird as well. Is the engine stumbling or choking out? Black smoke out the tailpipe when you rev the gas up? It could be the mass airflow sensor as well as if it has malfunctioned and is reading alot of air flow it will dump in more fuel as well....99 K1500 Suburban LT "THE BEAST"
Hypertech III, K&N, true dual
02-07-2012, 11:54 PM #6
I noticed a dramatic drop in mpg of my 2003 Silverado 5.3 2wd as well recently. Did you find out the problem??
02-23-2012, 08:15 AM #7
FYI, I had my transmission serviced, and my mileage has returned to normal levels.....Life is like a CRAP sandwich, The more bread you have, the less CRAP you have to eat....
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