I have 97 4.2 and I keep getting the Bank2 upstream code. I've replaced and still get code. Whatelse could the problem be.

 

Check the wires that go to o2 sensor. Make sure not cut or melted.

 

You should look for possible problems that are causing the ox2 sensor to throw a code. for starters, change the air filter and clean the MAF valve with a MAF valve spray (available at Auto zone an others). You could also have a vacuum in the air inlet downstream from your MAF valve. Replace you PCV Valve (less than $10) and make sure the hose attached to the PCV is not leaking or collapsed. Good luck.

 

Thanks Frank I'll check that when I get off.

 

thanks jstockert I checked the wires they were fine.

 

Most O2 sensor code are from a lean condition from a vac leak some where. You need to look for that first. check the PCV hose they are bad about getting holes in them. You will hear a his noise from them while the engine is running.

 

I replaced O2 sensors, PCV, cleaned MAF and K&N airfilter. Still getting code.

 

What code is it?

 

I keep getting O2 sensor bank 2 upstream.

 

What is the code number?