2008 Suburban - 170,000 miles
Transmission replaced - 2 months ago
Runs great
Rarely it has a Mild Vibration when at idle for 1 minute or less then it's gone
Check engine comes on but will go off after a week
Had a stuck lifter fixed 2 years ago (15,000 miles ago)
Have been driving it for 2 months with these codes (1,500 miles)
Showing Codes:
P0151: O2 sensor bank 2
P0174: System too lean bank 2
P0300: Random Multiple misfires
P2273: O2 sensor stuck Bank 2
I replaced the plugs and wires. Did not fix the problem

Any ideas?

 

Codes are telling you whats wrong. O2 sensor bank 2

 

Vibration at idle indicates a misfire, thus the code. Continued driving will just make things worse until enough unburnt fuel from the multiple misfires destroys your catalytic converters.

If the CEL has been flashing this whole time, it may already be too late.

 

Never hurts to ask before replacing a lot of good parts. Maybe it was due for plugs and wires anyway.

It could be some work , but if you switched O2 sensors and the codes changed to the other bank , you have proven the problem is the O2 sensor.

 

You really have to monitor your O2 sensors and your fuel trims. Your typical OBDII reader can't do this. You may have bad O2 sensors or you could just have an intake manifold leak somewhere. You'll need a reader that can access the modules in your vehicle. I use the HyperTough HT200 available at walmart for $50. It's just a rebranded Autel MaxiAP AP200. Awesome tool for the money.

A poor man's way to check for an intake leak is to spray some brake parts cleaner (make sure it's the flammable kind!) around the various places where air could enter if a seal or hose or elbow is cracked or leaking. If the engine RPMs increase, you've found the leak. Check all hoses and fittings that hook to the intake including the brake booster hose and fittings