I have an 04 silverado ( lq4, cam, lts, x pipe, etc..) and i have been fighting an 02 sensor issue for a while now, I have them turned off at the moment and everything seems fine minus some driveabilty and fuel mileage. But if i turn them back on (with hp tuners) right now it will drive perfect for a few days and then i can fire it up randomly one time and bank 2 seems like its reading fresh air and throwing a ton of fuel at the motor, i have checked,replaced cleaned the ground at the back of the block and head and replaced 02s with no luck.


anyone else having a similar issue with any help or ideas on what else to check would be very appreciated.

 

Have you logged the voltage and compared bank to bank?