How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Ron Z. Your Own Question
Ron Z.
Ron Z., - Pontiac Tech -
Category: Pontiac
Satisfied Customers: 18972
Experience:  18+yrs experience. State Inspector and Pontiac Diagnostics
Type Your Pontiac Question Here...
Ron Z. is online now
A new question is answered every 9 seconds

G6: 60k on it..error codes..p0455

Customer Question

i have a 09 g6 with 60k on it. getting 3 error codes. they are p0461, p0463, p0455. any ideas?
Submitted: 6 years ago.
Category: Pontiac
Expert:  Ron Z. replied 6 years ago.

Welcome to! My name is DriveFast71(Ron) and I will do my best to answer all of your questions completely and accurately.


The P0455 is "EVAP System Large Leak Detected" - this can be something as simple as a loose, missing or faulty Fuel Cap. Even putting fuel in the vehicle while it is running will set this code. If the fuel cap check ok, do a visual inspection looking for any disconnected or ripped vacuum lines.


The P0461 and P0463 are both pointing to a fault in the Fuel Level Sensor (your fuel gauge should not be working correctly). Check the electrical connector at the top of the fuel tank going to the fuel pump assembly for any loose, broken or rubbed through wires. If the visual inspection checks ok, suspect a faulty Fuel Level Sensor (actually quite a common problem with GM fuel systems.). This sensor is mounted to the side of the fuel pump, inside the fuel tank.


Customer: replied 6 years ago.
Isn't it odd that all these codes showed up at the same time? Is there any chance they are related.. I've read that pontiac has trouble with the bcm which may cause faults.
Expert:  Ron Z. replied 6 years ago.
I'm not seeing any Service Bulletins or recalls on the issue. Like I say- it's a fairly common GM problem. If your Fuel Gauge on the dash isn't working correctly, along with the P0461/463 that's pretty much proof positive you need a Fuel Level Sensor. Chalk it up as an "unhappy coincidence". GM states the Fuel Level Sensors have a pre-mature fail rate due to additives in the fuel (yet, they do nothing about it... go fig). As the the P0455, again, just a "general" code saying there is a "large leak" in the EVAP (emissions control) system. Very commonly a faulty fuel cap. Check that it is tight. Check the rubber o-ring on the underside of the cap for and chips of cracks. Check the fuel filler neck for any chips or cracks or debris that is not allowing the cap to seal tightly.
Ron Z. and 3 other Pontiac Specialists are ready to help you
Customer: replied 6 years ago.
Great, thanks for the info!
Expert:  Ron Z. replied 6 years ago.
You're welcome! Have a great day!