Code P0306 2001 Chevy Suburban 1500 5.3L

Chevy Suburban 2005

I am getting code P0306 NO. 6 Cylinder misfire. I have changed out the injector, coil, spark plug wire & spark plug. My car is still running rough and code still shows up. What is wrong?

Chevy Code P0306

Chevy Code P0306 means that the cylinder 6 is misfiring or is randomly misfiring. Start by checking for intake leaks and if no leaks are found the next step is to replace the spark plugs on cylinder 6.

When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.

Chevy Code P0306 Possible causes

  • Faulty spark plug 6
  • Clogged or faulty fuel injector 6
  • Faulty ignition coil 6
  • Fuel injector 6 harness is open or shorted
  • Fuel injector 6 circuit poor electrical connection
  • Ignition coil 6 harness is open or shorted
  • Ignition coil 6 circuit poor electrical connection
  • Insufficient cylinder 6 compression
  • Incorrect fuel pressure
  • Intake air leak