code p0455
code p0455 I have a 2005 GTO with a STS on it. Every few weeks I get this code coming up p0455. I thought it was the gas cap but it's not, haven't changed anything recently. We have been having problems with popping on decel and surging while cruising. This time when the light came on I noticed the car was running better, no popping and cruises fine. When I clear the code it goes back to running like crap again until the light comes back on. Does the light coming on disable something? I can't figure out where this leak could be. Anyone know where it's most probable?
TECH Senior Member
Joined: Dec 2001
Posts: 5,399
Likes: 3
From: Jacksonville, FL
Don't know - to find the leak you're probably going to have to introduce smoke into the evap system. Friend of mine had an evap (small leak detected) code on his Z28 and that's how the shop found his. Don't understand why it would run worse after clearing the code. Have you looked at www.gearchatter.com/viewtopic11721.php
