I have a 05 trailblazer it had a p0304 code I replaced the following: coil pack, ignition coil, battery, fuel filter, water pump, timing solenoid, spark plugs, crank shaft sensor, iridium plug. It's still reading p0304, p0455, p0526, p0335 codes. It's running rough, doesn't want to stay started, funk smell from exhaust. Please help. Thank you

 

Did you just recently purchase fuel?

Could you have received a questionable load of fuel?

 

Did you perform or have a CASE relearn done after you replaced the crankshaft sensor? Anytime the crankshaft sensor is removed or replaced, a special procedure must be performed so that the differences between the crankshaft position sensor and the camshaft position sensor data is programmed into the ECM. NOTE - this procedure does not need to be performed when replacing the camshaft position sensor. If you did not do the CASE relearn, then the engine can run rough. This is likely why you are getting the P0335.

The P0455 is telling you that there is a problem with the EVAP canister vent valve circuit.

The P0526 is telling you there is a problem with the electronic fan clutch and a failure with it's speed sensor circuit.

The P0304 is saying you still have a miss on cylinder 4. Check to make sure that the electrical connector to the ignition coil is properly seated and also that the ignition coil is properly seated on the spark plug. Also, check to make sure the electrical connector to the fuel injector is properly seated.

Good Luck!