Possible causes – Dirty engine oil– Low engine oil level– Faulty exhaust valve control solenoid– Exhaust valve control solenoid harness is open or shorted– Exhaust valve control solenoid circuit poor electrical connection When is the code detected? ECM monitors OCV

Possible causes – Dirty engine oil– Low engine oil level– Faulty intake valve control solenoid– Intake valve control solenoid harness is open or shorted– Intake valve control solenoid circuit poor electrical connection When is the code detected? ECM monitors OCV

Possible causes – Dirty engine oil– Low engine oil level– Faulty intake valve control solenoid– Intake valve control solenoid harness is open or shorted– Intake valve control solenoid circuit poor electrical connection When is the code detected? ECM monitors OCV

Possible causes – Dirty engine oil– Low engine oil level– Faulty Oil Control Valve– Engine mechanical problems Symptoms – Engine Light ON (or Service Engine Soon Warning Light)– Lack/Loss of power– Engine rough idle P0021 KIA Description The CVVT (Continuously

Possible causes – Dirty engine oil– Low engine oil level– Faulty Oil Control Valve– Engine mechanical problems Symptoms – Engine Light ON (or Service Engine Soon Warning Light)– Lack/Loss of power– Engine rough idle P0021 2008 KIA OPTIMA Description The

Possible causes – Dirty Fuel Injector 1– Faulty Fuel Injector 1– Plugged Fuel Injector 1– Fuel injector 1 harness is open or shorted– Fuel injector 1 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 1– Faulty Fuel Injector 1– Plugged Fuel Injector 1– Fuel injector 1 harness is open or shorted– Fuel injector 1 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 2– Faulty Fuel Injector 2– Plugged Fuel Injector 2– Fuel injector 2 harness is open or shorted– Fuel injector 2 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 2– Faulty Fuel Injector 2– Plugged Fuel Injector 2– Fuel injector 2 harness is open or shorted– Fuel injector 2 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 3– Faulty Fuel Injector 3– Plugged Fuel Injector 3– Fuel injector 3 harness is open or shorted– Fuel injector 3 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 3– Faulty Fuel Injector 3– Plugged Fuel Injector 3– Fuel injector 3 harness is open or shorted– Fuel injector 3 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 4– Faulty Fuel Injector 4– Plugged Fuel Injector 4– Fuel injector 4 harness is open or shorted– Fuel injector 4 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 4– Faulty Fuel Injector 4– Plugged Fuel Injector 4– Fuel injector 4 harness is open or shorted– Fuel injector 4 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 5– Faulty Fuel Injector 5– Plugged Fuel Injector 5– Fuel injector 5 harness is open or shorted– Fuel injector 5 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 5– Faulty Fuel Injector 5– Plugged Fuel Injector 5– Fuel injector 5 harness is open or shorted– Fuel injector 5 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 6– Faulty Fuel Injector 6– Plugged Fuel Injector 6– Fuel injector 6 harness is open or shorted– Fuel injector 6 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 6– Faulty Fuel Injector 6– Plugged Fuel Injector 6– Fuel injector 6 harness is open or shorted– Fuel injector 6 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 7– Faulty Fuel Injector 7– Plugged Fuel Injector 7– Fuel injector 7 harness is open or shorted– Fuel injector 7 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 7– Faulty Fuel Injector 7– Plugged Fuel Injector 7– Fuel injector 7 harness is open or shorted– Fuel injector 7 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause

Possible causes – Dirty Fuel Injector 8– Faulty Fuel Injector 8– Plugged Fuel Injector 8– Fuel injector 8 harness is open or shorted– Fuel injector 8 circuit poor electrical connection Tech notes Clogged or partially clogged fuel injector can cause