- Dec 24, 2012
- 34
Recently bought an '06 Silverado; crew cab, 5.3, 4X4- with around 112.5k. CEL came on and took it to have it scanned. Said that all 4 O2 sensors are bad, and the vapor canister vent solenoid crapped out, too. I already have the solenoid, so my question is; Is there any difference between upstream and downstream sensors, can I buy 4 of the same sensors and use them, or do I have to purchase 2 downs and 2 ups?