Questions and Answers

Ford Escort PFE Sensor Q. Hi Vincent, I enjoy your informative site: First time user. What is a PFE sensor and what is its function? It was recently replaced. Are they prone to failure in these cars? I have driven this car for about two years and recently added a fuel injector cleaner to the gas tank.

This is the first time Ive added anything other than gas line antifreeze to the fuel tank. Is there a link between using fuel injector cleaner and sensor failure? Please advise. Thanks.

1998 Ford Escort Station Wagon SE
2.0 liter
Automatic
90,000 kilometers or 54,000 miles
Fuel injection

Best regards,
Bill

A. The EGR system is Differential Pressure Feedback Exhaust Gas Recirculation, controlled by the Powertrain Control Module (PCM) and comprised of the following components:

• DPFE Sensor (Also called the Back Pressure Transducer (BPT).)
• EGR Vacuum Regulator (EVR) Solenoid
• EGR Valve

The DPFE Sensor controls vacuum applied to the EGR control valve. This allows the operation of the EGR control valve to be controlled by actual engine operating conditions.

Since a very small amount, and I mean really small amount, of exhaust gas is allowed to enter the DPFE it is, theoretically possible for a fuel additive to damage the DPFE. But I really don't think that is what caused the failure.