P1131-1996 Mercury Mystique

Question

is a 4cyl zetec 1996 mercury mystique. 111,000km

Answer 1

HI there,

This code means there is a lack of switch on the heated O2 sensor, bank 1,sensor 1. It's stuck on the lean side. This usually means the problem on these is a vacuum leak at the hose for the pcv valve