I heard that if the gas cap does not provide a good vacuum, then performance will drop and according to the Contour manual the CEL will reset itself after three engine restarts.
I'm no mechanic, so take what I say with a grain of salt.
1996 Contour SE Sedan 4D (Royal Blue)
Duratec V6 2.5L 24-valve DOHC
Automatic
75,000 miles
No Mods (unless you call the DMD a mod)
Replaced EGR valve (gunked up), EVR (EGR VR), PCV valve, and evaporative emissions hose (cracked).
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