Mechanics

GRAND CHECK ENGINE LIGHT COMES ON

1996 Mercury Marquis • V8 2WD Automatic • 42,000 miles

1996 Mercury Grand Marquis mileage: 42,000. Every several hundred miles or so (between code clearing), the check engine light will come on. The codes are 0171 and 0174 indicating a lean condition. Gas mileage is also down about 10%. I have replaced the fuel filter, fuel pressure regulator (fuel pressure is 31 psi with vacuum and 42 psi without) and EGR valve. I have also tuned the car replacing plugs, plug wires and air filter. Any ideas as to what is triggering the codes?
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2CarPros-Archives
November 19, 2010.



Try replacing the oxygen sensors.

Tiny
2CarPros-Archives
Nov 19, 2010.