Check engine light - code: p1131

1999 MERCURY COUGAR
95,700 MILES • 6 CYL • FWD • AUTOMATIC
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ASHLEYD01
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My 1999 Mercury Cougar has the CE light on and the code read p1131. I can't afford to take it in to a shop right now, so what do I do to fix this?
Dec 4, 2010 at 12:50 PM
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RASMATAZ
  • ✓Experienced Mechanic
  • 75,992 POSTS
DTC P1131 indicates the system is correcting RICH for an overly LEAN condition. The Heated Oxygen Sensor (HO2S) voltage is less than 0.45 volts. This is usually due to a vacuum leak after the MAF. It can also be caused by a bad PCV valve or PCV system hose.

It can also be caused by low fuel pressure or a plugged injector.

Dec 4, 2010 at 12:53 PM
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ASHLEYD01
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  • 2 POSTS
How do I fix this?
Dec 4, 2010 at 2:20 PM
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