My check engine light came on today and Autozone pulled 3 codes. The first is PO125 and there are two "old" codes P1130 and P1135. From reading some posts here I'm guessing that the PO125 is the O2 sensor? Every post I read says its the bank 1 sensor. Is this the first O2 sensor on the manifold (pre cat)? Also I have no idea what the other 2 codes are and if I should be concerned since they are "old" codes. Any help would be appreciated. Oh yeah I have a 2000 Limited with 106K. Thanks.
Engine codes
- Thread starter Mojo29
- Start date
Register to hide this ad
TheDurk
Elite Member
All those codes are related to your Air/Fuel (front) sensor. Change it and they should all go away.
Look up your Denso part number here: DENSO Aftermarket Online Catalog | Vehicle Parts Search Probably 234-9002.
Denso is the manufacturer of the OEM sensors. Then Google the part number as Denso ####### and as Denso ###-####. Go for the best price. Be sure to check Amazon and rockauto.com. Amazon is usually the cheapest.
Do not buy Bosch, only Denso. If you live in the snowbelt you will want two new nuts from the dealer #90179-08059 or M8-1.25 stainless nuts anywhere you can find them.
Look up your Denso part number here: DENSO Aftermarket Online Catalog | Vehicle Parts Search Probably 234-9002.
Denso is the manufacturer of the OEM sensors. Then Google the part number as Denso ####### and as Denso ###-####. Go for the best price. Be sure to check Amazon and rockauto.com. Amazon is usually the cheapest.
Do not buy Bosch, only Denso. If you live in the snowbelt you will want two new nuts from the dealer #90179-08059 or M8-1.25 stainless nuts anywhere you can find them.
Last edited:
TheDurk
Elite Member
TheDurk
Elite Member
You are getting the upstream sensor which is $103, I hope. The $60 one is downstream (Bank 1 Sensor 2) which is NOT what you need. Right?
I think the correct part number and this is for the O2 is Denso 234-4162. The Autosone code reads P1130 "air fuel sensor circuit range/performance" and P1135 "air/fuel sensor heater circuit response". Not that I trust Autozone because the guy who scanned it said it a temperature sensor located on the radiator. I question his expertise..
You need to find out first if you have a Ca emissions vehicle or not. It doesn't matter if the vehicle is in or has ever been to Ca it could still be a Ca emissions vehicle. Check both under the hood and on the door sill to see if it is a 49 state legal vehicle or Ca.
The Ca emissions vehicle will require a Air/Fuel sensor in the front that is quite a bit more expensive than the O2 sensor that the 49 state emissions vehicle will need. If you do purchase the wrong one, you will find out as soon as you try to plug it in. These two sensors have different plugs to prevent them from being used interchangeably.
Looked at the door sill and it didn't say squat. However under the hood there is a sticker that reads " This vehicle conforms to the U.S. EPA NLEV regulations applicable to gasoline fueled 2000 model new LEV light duty trucks and to california regulations applicable to 2000 model year new LEV light duty trucks". So does mean I need the Cali verison of sensor which would be the air/fuel sensor not O2? Im confused as hell at this point.
TheDurk
Elite Member
That's my fault. I had it in my head you were a 2001 which would have made it air/fuel no matter what. You have a 49-state Federal. No air/fuel just O2. The Cali label has a lot more BS about "introduced for sale in the state of California....blah...blah."
Count your cats just to be sure. One cat = Federal. Two = Cali. Second one is almost vertical on the way up to the engine, if you have one.
Last edited:
I do have 2 cats. The exhaust from the drivers side runs behind the engine and then ties into a y pipe into the first cat. It then runs to the second cat along the passenger side. I did manage to unclip the sensor from the harness which is a pain and I compared the harness to the cali version (online) and appears identical. I ordered the Denso cali version and I guess we'll see what happens when it comes in. The non cali version had a similar but different harness.