07 Tahoe w/ 5.3 purchased used a few months ago. CEL comes on when idling for roughly 5 mins or so. I've checked the code and every time it's P0302. After purchasing the vehicle I changed plugs and wires, and changed oil. After CEL came on I verified wire and plug were installed correctly on cylinder 2. This weekend I checked voltage to the coil, but didn't have an HEI spark tester so I swapped #2 coil with #4 coil to see if the problem followed the coil. Yesterday I intentionally let truck idle to trigger the CEL, which it did come on. I checked the code, still P0302.
CEL came on before spark plug change as well. Gas is routinely 91.
At this point I'm ready to take it to dealership or qualified mechanic to diagnose since I'm not sure what else to do. What else can I check before going that route?
I want to run fuel system cleaner through it just to see what happens.
CEL came on before spark plug change as well. Gas is routinely 91.
At this point I'm ready to take it to dealership or qualified mechanic to diagnose since I'm not sure what else to do. What else can I check before going that route?
I want to run fuel system cleaner through it just to see what happens.