Chevy Trailblazer P0455- EVAP Large Leak

2004 Chevy Trailblazer 4.L inline 6 cyl Codes p0455. What should i be looking for when code p0455 comes up....evaporative emission control system leak detected (gross leak)

Answer:
Code p0455 is a large EVAP leak. A common cause for this is a loose or faulty gas cap. Or if the truck was running when you were filling it with gas, this can also cause this code.

Another common cause is a faulty / sticking EVAP vent solenoid / valve. If the vent valve does not operate, the system will not seal when it needs to, thus causing a large leak. A simple test with a test light and a scanner that can turn the vent solenoid on and off would need to be done to test the valve.


 

Question:
My 2002 trailblazer is having electrical issues. The hatch and window is locked closed, the remote doesn't work and the radio doesn't stay on after the car is turned off.

Answer:
There is a computer located in the tailgate, called the Liftgate Module. These are known to go bad and cause the issues you describe. If the tailgate is locked and you can't open it, you will have to try to remove the trim panel from the inside and then manually unlatch the tailgate lock. You should have the vehicle checked for any trouble codes and if there is communication with the Liftgate Module. If it is needed to be replace, it will have to be programmed at a dealership to be fully functional. Be sure to check all fuses, including the fuse box underneath the left rear seat. Your remotes will have to be reprogrammed as well. You may also want to try disconnecting the battery for about 10 minutes and see if that helps too.

Problem with my 2002 Chevy Trailblazer.
New times put on within 2,000 miles ; car inspected December 2009 Question: DRIVING AT 45 MPH AND ABOVE I HEAR A HIGH PITCH HUM FROM REAR PASSENGER WHEEL. THERE ARE NO VIBRATIONS WHATSOEVER. VEHICLE RECENTLY PASSED INSPECTION 12/09.

Answer:
Try popping it into neutral as the noise is occurring. Be sure to let off the gas. This will tell you if it is related to vehicle speed, or engine speed. If the noise continues the same, you may have a noisy bearing in the rear differential. If the sound changes, then it is an engine frequency noise. Possibly exhaust heat shield, exhaust hitting frame, rear end housing or suspension component.

Question: i want to know how long or what to do if the code P0455 came out after filling gas while the engine is running. Do i need to do something. Or where is the vent solenoid is located?
 Answer: If indeed the gas cap was the cause of the check engine light code P0455, then it will go off by itself after several starts, driving, off time and restarts. All codes have different parameters for running the system test. You could try to disconnect he battery for a few minutes, or go to one of the large national parts store chains and have them clear it for free.

Question: 2006 Trailblazer P0442 code and P0455. No leaks. What should i check next. I tested that vent tube sent power with my problem and it closed. Plug it in it stays open. Is this the problem?
 If you have a P0442 and P0455, you definitely have an EVAP leak somewhere. The proper way to check is with a pressurized smoke/nitrogen machine, which you most likely do not have access to. The 455 is a 'large leak' and is usually the vent valve back at the gas tank. Even if you can hear it 'click' that doesn't mean it's not leaking. The 442 could have set as a result of the 455 or be something different, like a gas cap that isn't sealing, or a purge solenoid that doesn't quite shut off, or a leak in one of the EVAP lines somewhere. I'd start by replacing the vent valve, they aren't very expensive, then clear the codes and see if your problem persists.


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