P0304 CADILLAC Cylinder 4 Misfire Detected

Possible causes
– Faulty spark plug 4
– Clogged or faulty fuel injector 4
– Faulty ignition coil 4
– Fuel injector 4 harness is open or shorted
– Fuel injector 4 circuit poor electrical connection
– Ignition coil 4 harness is open or shorted
– Ignition coil 4 circuit poor electrical connection
– Insufficient cylinder 4 compression
– Incorrect fuel pressure
– Intake air leak
Tech notes
The P0304 code means that the cylinder 4 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 4. If the problem persist more tests needs to be done to diagnose problem, see “Possible Causes”
When is the code detected?
Engine Cylinder 4 is Misfiring.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– Lack/loss of power
– Hard start
– Engine hesitation
P0304 CADILLAC Description
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.
CADILLAC Technical Service Bulletins for P0304 code
2007 CADILLAC ESCALADE ENGINE AND ENGINE COOLING:ENGINE
2007 CADILLAC ESCALADE ESV ENGINE AND ENGINE COOLING:ENGINE
2007 CADILLAC ESCALADE EXT ENGINE AND ENGINE COOLING:ENGINE
2007 CADILLAC ESCALADE FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2007 CADILLAC ESCALADE ESV 1500 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2007 CADILLAC ESCALADE EXT 1500 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2008 CADILLAC ESCALADE FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2008 CADILLAC ESCALADE ESV 1500 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2008 CADILLAC ESCALADE EXT 1500 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2004 CADILLAC CTS ENGINE AND ENGINE COOLING:EXHAUST SYSTEM