So I'm constantly getting the P0420 code on my 2000 Durango 4.7L with 189,000 miles. Original O2 sensors.

I haven't looked yet but I figure I have one O2 sensor pre cat and one post cat being that it's a non California emissions setup.

No idea which one's to get from Rock auto website or how many:

https://www.rockauto.com/en/catalog/...2)+sensor,5132

 

NTK or Denso brand only please. Pay attention to which emissions package as well. You may have two upstream, and one or more downstream, even on a federal emissions truck.

 

Like HeyYou said, unfortunately, your truck will have 4 in all, two on each bank, so you have to get upstream and downstream for each side. Stay away from Bosch.

Mine haven't complained even with 306K miles. I'd like to replace them cause I know it's overdue and I'd like to see their effect on gas mileage, but it's four of em, so recovering the cost in fuel savings would take forever. Personally, I'd remove the plastic fender wells for the upper sensors. The sacrificial clips and tool that hold the wheel well in can bought at Harbor freight, but zip ties have worked really well for me.

PS: Start spraying them with PB blaster from now and let it soak in overnight before driving. Dakota and Durango procedure will be the same.

 

I only see two. One pre cat and one post cat.

Mine are shot because of a previous oil leak. Valve stem seals got replaced. Unfortunately the sensors didn't survive.

 

Are you looking at both pipes?

 

Yep. Only two.

On a side note the check engine light went off.

 

iirc po420 is for bank 1 po430 is for bank 2

watch the 02 switching rate. when warmed up and at 2500rpm, the front should be switching fast, the rear slow. if they are both switching fast and at the same rate...you probably need a cat. if the front is switching slow...you need a sensor

 

Hopping in on this question, but its kind of an off shoot...HeyYou mentioned NTK or Denso brand, does that translate to other sensors such as Idle Air Control for brands? Did not see a "Mopar" branded one of Rock Auto...

Sorry for the but hopefully this will catch HeyYou's eye

Steve

 

You can find the mopar brand IAC at various places, and you REALLY want the mopar feller there..... Look up the part number for the mopar piece, then just google search on that. It will give you a LOT of options.

 

Sorry, I'm not HeyYou....

...but I did buy a Mopar IAC on Amazon some months back....


and Rock Auto does have it....

https://www.rockauto.com/en/parts/mo...ac)+valve,6072