i have the codes from the scanner but i dont know what they mean. the first one is po171/ popo443/ po304.

Asked by Jun 29, 2014 at 04:02 PM about the 1999 Mercury Cougar

Question type: Maintenance & Repair

i just like to find out why my engine light wont go out. i have to smog my car in june so i need to fix this asap can you please help me. thanx tanya

4 Answers


Sounds like you have a vacuum leak. Code P0171 is a lean condition. Code P0443 is the EVAP system purge valve is malfunctioning. Code P0304 is a misfire on cylinder number 4. HTH. -Jim

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http://www.obd-codes.com/p0171 -- check this out for possible causes and solutions.

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