B0728 Mazda Rx-4 Diagnostic Trouble Code

B0728 Mazda Rx-4 code definition:
B0728 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code for Mazda Rx-4.

B0728 Mazda Rx-4 or the Evaporative Emission Control System Incorrect Purge Flow is the set whenever the computer sees that there is a problem with the flow coming from the purge valve or the purge flow is not enough within the EVAP system. So if the problem persists despite of your diagnosis, then you should never hesitate to take your vehicle to your dealer or to a qualified mechanic.

Symptoms

Symptoms of a B0728 Mazda Rx-4 diagnostic trouble code may include:

Engine surge
Blown fuse (if applicable)
Lack of power
Rich or lean exhaust

Possible Causes :

Faulty IMRC actuator relay (if equipped)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Rarely - faulty Powertrain Control Module (PCM-programming required after replacement)

Common Misdiagnoses

TP Sensor Learn Not Complete Problem
Low Coolant Circuit Problem
Cruise Control System - Vehicle Accel Too High Problem
TFP Valve Position Switch-Drive Without Drive Ratio Problem
Problem

Repair Processes :

Use the DVOM to test resistance and continuity on all system circuits if actuator and sensor resistance levels are in compliance with manufacturer's specifications. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Look at the plug wires to make sure they are not burnt or laying on the exhaust.

Process Tips

Diagnostic trouble code B0728 Mazda Rx-4 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before B0728 Mazda Rx-4.

Fortunately, B0728 Mazda Rx-4 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.