Hi, my 97 Expedition (4x4 5.4L) 's check engine light is on.

Code reader shows p0133 which means O2 sensor Circuit Slow Response Bank 1 Sensor 1.

Is this means I need to replace the O2 sensor?

Is Bank 1 the driver side or persenger side?
Is Sensor 1 before or after the cat?

Thanks in advance for you help

Kam

 

Have you found out where the location of the oxygen sensor is when the ODBII tester referes to Bank 1 Sensor 1. My truck has the same issue.

I also have 1 and 2 misfiring along with other things. So I guess I could cross reference which side cylinder 1 and 2 is on, but thought I would ask you to see?

 

Bank One is a multinational bank holding company in the process of merging with JP Morgan Chase......

Bank 1 is the driver side #1 is upstream. IF one has failed, you might as well replace the pair of upstream units at the same time. They are normally good for 80K to 100K miles.

 

Just wondering if it's a PITA to change the sensors? and if not, any special tools required? I'm around 112k and I don't think any have been changed since the truck was new (checked all the receipts). I've just changed my plugs this past weekend, and you want to talk about a PITA!

Thanks,
Phil

 

I've heard the passenger side is tough to get to and might require removal of some nearby components. If you were able to do the plugs, you should be able to tackle this too.