1. Rough idle is due to a misfire caused by loss of spark, fuel, or compression. That's an obvious cause of loss of power and the need to push harder on the gas pedal.
2. Leaking fuel pressure regulator.
3. Dragging brakes.
All of the potential causes depend on what you mean by "poor fuel economy. Is it down by four miles per gallon or are you getting four miles per gallon?
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Wednesday, September 19th, 2012 AT 7:33 PM