P1B77 Dodge Spirit Diagnostic Trouble Code

P1B77 Dodge Spirit code definition:
P1B77 is a kind of OBD-II Diagnostic P-Powertrain Diagnostic Trouble Code for Dodge Spirit.

P1B77 Dodge Spirit shows up when there's an electrical problem that causes the fuel volume regulator to malfunction and open. It's quite an unusual problem and likely intermittent. Other serious codes may cause this code to pop up, and they may come with dangerous drivability issues that may expose you to safety risks and cause damage to the engine in the long run.

Symptoms

Symptoms of a P1B77 Dodge Spirit diagnostic trouble code may include:

Fuel pressure too low
Rich or lean exhaust
Diminished fuel efficiency
Reduction in engine performance, especially at low RPM levels

Possible Causes :

A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area.
Some aftermarket accessories and performance modifications
Faulty IMRC actuator/sensor

Common Misdiagnoses

IC Circuit High Voltage Problem
Control Module Throttle Actuator Position Performance Problem
Air Conditioning (A/C) Clutch Feedback Circuit High Voltage Problem
Cruise Vehicle Speed/Set Speed Difference Too High Problem
PCM Stack Overrun Problem

Repair Processes :

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. Once located, visually inspect the connectors and wiring. Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors. Replace the oxygen sensor that is downstream from the catalytic converter on the side of the engine that does not contain cylinder #1. Also, if a oxygen sensor code stating "heater circuit malfunction" the sensor has most probably failed.

Process Tips

Diagnostic trouble code P1B77 Dodge Spirit 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 P1B77 Dodge Spirit.

Fortunately, P1B77 Dodge Spirit is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.