Mercury Grand Marquis White Exhaust Smoke: Causes, Diagnosis, How to Fix

If you own a Mercury Grand Marquis, you may have noticed white exhaust smoke coming from your car on occasion. This can be concerning, and it’s essential to understand the possible causes behind this phenomenon to address the issue promptly and efficiently. Several factors can contribute to white smoke emanating from your car’s exhaust pipe, … Read more

Mercury Grand Marquis Troubleshooting:  Squeaky Brakes

  Your Mercury Grand Marquis‘s braking system is designed to handle thousands of miles of braking with no intervention from you.  When its brakes begin to squeak, they are telling you that they need some attention. The most typical cause of squeaky brakes are the brake pads themselves, but there are other issues that can … Read more

Mercury Grand Marquis P0421 Code: Meaning, Causes, How to Fix

P0421 is a relatively rare OBDII trouble code.   It’s generic, which means it has the same definition for the Mercury Grand Marquis as it would any other vehicle. It is technically defined as “Warm Up Catalyst Efficiency → Below Threshold (Bank 1)”. In layman’s terms, it indicates that your Mercury Grand Marquis’s catalytic converter is not scrubbing … Read more