U204C Alpine A110 Diagnostic Trouble Code

U204C Alpine A110 code definition:
U204C is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code for Alpine A110.

U204C Alpine A110 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. The PCM then uses this data to provide the right strategies for the fuel delivery and ignition timing of the engine.

Symptoms

Symptoms of a U204C Alpine A110 diagnostic trouble code may include:

Fuel pressure too low
Rich or lean exhaust
Diminished fuel efficiency
Engine surge

Possible Causes :

Rarely - faulty Powertrain Control Module (PCM-programming required after replacement)
Rough running engine due to misfiring plugs. Many engines have misfire codes to indicate the cylinder effected, such as P0307 for number 7.
Faulty IMRC actuator/sensor

Common Misdiagnoses

Crankshaft Position Sensor Circuit Performance Problem
TP Sensor Learn Not Complete Problem
Low Coolant Circuit Problem
Cruise Control System - Vehicle Accel Too High Problem
Kick-Down Switch Failed Short Problem

Repair Processes :

Look for missing ground strap or a rusty ground where the fuel tank is grounded to the frame. Check for damage to the wiring harness connector. If all testing has passed so far yet you still have the same code, check your scan tool and see if it can open and close the IMRC valve. Look at the plug wires to make sure they are not burnt or laying on the exhaust.

Process Tips

Diagnostic trouble code U204C Alpine A110 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 U204C Alpine A110.

Fortunately, U204C Alpine A110 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.