C1818 Diagnostic Trouble Code

C1818 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a C1818 diagnostic trouble code may include:

Faulty or damaged wiring
The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly
Poor fuel economy
Diminished fuel efficiency

Possible Causes :

The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture.
Defective ECU strategies or components will prevent proper regeneration
A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture.

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.

Process Tips

Diagnostic trouble code C1818 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 C1818.

Fortunately, C1818 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C1818 Trouble Code For Specific Cars

C1818 Skoda Octavia Ii Knock Sensor 2 Circuit High Input (Bank 2)
C1818 Isuzu Ascender
C1818 Glas 1500 Overdrive switch circuit short to Vbatt
C1818 Matra-simca M Transmission Over Temperature Condition
C1818 Tatra T700 Mirror Switch Invalid Code
C1818 Alldays 30 Air Bag Memory Clear Circuit Failure
C1818 Siata 750 Intake Air Temperature Sensor 2 Circuit Intermittent/Erratic