PO156 Code!! Help!

[98expy98]

Hello! i am new to the forum. Its been SUCH a help already!

okay, so i bought a 1998 expedition xlt 4.6 about two weeks ago. the CEL was on, got the codes off, and saw that it was one of the CO2 sensors, So i ran down to the parts store picked one up and threw it in. cleared the codes and everything went well. About 10 miles later the CEL came back So i checked the codes and yet again it came up P0156 Bank 2 Sensor 2. I crawled back underneath and double checked that it was tight and that the plug was securely in its home, in which it was. So the code is still on and i replaced the sensor as it said it needed replacing. I have also noticed that it has a very slight vibration at idle with a small amount of acceleration. Not sure what to do next and i am hoping to suck some knowledge from you fellow expy enthusiasts. Thanks In Advance

 

[jbanks]

code po156,will not go away. - Ford F150 Forum

Looks like, Exhaust Leak, Messed up Wiring or bad PCM are options

 

[bedrck46]

Just to make sure as I have noticed some confusion as to which side is Bank 1 and Bank 2
Passenger or Driver side.
Which side did you change??

 

[98expy98]

Passenger side after the cat??

 

[bedrck46]

Bank 2 sensor 2 is the drivers side after the cat

 

[98expy98]

And i have checked all around the exhaust system and it has no leaks to be found.

 

[bedrck46]

but it appears you changed the wrong sensor

 

[98expy98]

NO WAY!! I called my local ford dealership, and the parts manager assured me it was the passenger side

 

[98expy98]

i will replace the driver side sensor and let you guys know. Thanks

 

[bedrck46]

seems as if you doubt me Google it and see what comes up at least double check

 

[bedrck46]

Also you may want to clean out the exhaust ports in the throttle body Look on you- tube as there is a good video that shows just how clogged the ports can get Had that happen on my last 99 and the amount of carbon that was in the ports could have filled up 2 shot glasses or more made a difference when cleaned but that wasn't the total fix had to replace the DPFE sensor also.