C0421 Mazda Auto Trouble Code

C0421 Mazda OBD2 specifically refers to the camshaft (cam) timing. In this case, if the cam timing is over-retarded, the engine light will be illluminated and the code will be set.

Evaporative emissions systems test for a leak in the fuel tank and associated hoses. To perform the test, the computer pulls a vacuum and checks to see if the vacuum holds. Each car maker uses a different techniques to check, but most often it's some type of fuel tank pressure sensor.

C0421 Mazda Possible Solution:

Disconnected, dirty or fouled spark plugs are common causes for engines that won't start. Spark plugs typically need to be replaced every season or 25 hours of use. You should also check that the spark plug gap is set properly. If your spark plugs look good, problems with your ignition system can also preventing a spark. These can range from a faulty spark plug lead, shorted kill switch or flywheel key damage.

C0421 Mazda Description For All Models :

C0421 Mazda Trouble Repair :

When you turn on the ignition, the Service Engine Soon or Check Engine C0421 Mazda light should flash briefly, indicating that the OBD system is ready to scan your vehicle for any malfunctions. After this brief flash, the light should stay off while you drive as long as no problems are detected. You'll be glad to know that your vehicle is equipped with an early warning system that could save you time, money, and fuel in addition to helping protect the car!

Code Search

Please fill the search bar to find Auto Trouble Code meaning.

Example: 0120