1998 Mercury Sable P0174 Code: Diagnosis and Solutions After Replacing MAF, Injectors, and Vacuum Components
I own a 1998 Mercury Sable that has been displaying the P0174 diagnostic trouble code. The issue initially manifested with a flashing check engine light and a P0305 misfire code (cylinder 5). I replaced the spark plugs, ignition wires, and coil pack for cylinder 5, which cleared the P0305 but triggered the P017
Check fuel pressure levels or share your fuel trims data. Also, measure the voltage output from each oxygen sensor — especially the downstream O2 sensor. Try performing a 'system rich' test to observe sensor response. Consider using an injector cleaner like SeaFoam as a supplementary step. For more details on P0174 in 1998 Mercury Sable models, refer to: https://www.obd-codes.com/p0174