1999 cougar 2.5, cel on, codes p1131,p0171
Year : 1999
Make : Mercury
Engine: 2.5 V6 A/T
checked for vacuum leaks, none found
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If there are no vacuum leaks, this is more than likely a problem with the o2 sensor.
I was leaning in that direction. Just wanted confirmation.
Yea, the MAF is possible, but the o2 sensor is most likely.
When these 2 codes are together history shows o2 sensors have fixed the problem.
DO you have a scan tool?
Get back to me when you can
Sorry. Had to attend to other business. Replaced 1 1 o2 sensor, erased code and road tested extensively. No cel so far. Sent customer on his way. Hoping for the best. I do have a scan tool that gives me data. What did you have in mind? For future reference. Thanks, Customer
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