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O2 sensor on 07 TB 6cyl

240 Views 9 Replies 6 Participants Last post by  metalmike187_5978
Greetings all. I have a question in regards to the 02 sensors. She threw the code for 02 sensor, but of course, it can't say upstream or downstream. This is my 3rd TB. Both previous TB's had same code, I only replaced downstream both times, code disappeared. My question is, is it okay to replace only downstream if code disappears after changing, and when, or if, I should also do upstream sensor despite no code. Always get the best advice here for my TB. Thanks all 馃憤
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Exactly what was the code? The code will identify which O2 sensor circuit is misbehaving.

FYI, Diagnostic Trouble Codes (DTCs) do not tell anybody if a part is bad. DTCs tell you there is a problem with a circuit or a system.
Greetings all. I have a question in regards to the 02 sensors. She threw the code for 02 sensor, but of course, it can't say upstream or downstream. This is my 3rd TB. Both previous TB's had same code, I only replaced downstream both times, code disappeared. My question is, is it okay to replace only downstream if code disappears after changing, and when, or if, I should also do upstream sensor despite no code. Always get the best advice here for my TB. Thanks all 馃憤
Greetings all. I have a question in regards to the 02 sensors. She threw the code for 02 sensor, but of course, it can't say upstream or downstream. This is my 3rd TB. Both previous TB's had same code, I only replaced downstream both times, code disappeared. My question is, is it okay to replace only downstream if code disappears after changing, and when, or if, I should also do upstream sensor despite no code. Always get the best advice here for my TB. Thanks all 馃憤
Exactly what was the code? The code will identify which O2 sensor circuit is misbehaving.

FYI, Diagnostic Trouble Codes (DTCs) do not tell anybody if a part is bad. DTCs tell you there is a problem with a circuit or a system.
After AutoZone erased the codes, after telling me it was an 02 sensor. I went out earlier and got my own OBD2 reader. She is currently throwing P0030 and P0053. Book says heater circuit, not 02. I am confused, or was AutoZone trying to B.S. me for a sale? Thanks Chem_man!!
Thank you for the codes. Regarding AutoZone, ask yourself this simple question - "What is AutoZone in business for?" Unfortunately, many of the employees at AutoZone, Advance Auto Parts, O'Reilly Auto Parts, etc. really know very little about working on automobiles and even less about the On-Board Diagnostics (OBD II) systems. You did the right thing - you purchased your own OBDII code reader! Congrats!

OK, here goes the explanation of the codes, a little tutorial and what you need to do to proceed.

P0030 is telling you that there is a problem with the Heater Control Circuit which is located in the Bank 1 Oxygen Sensor 1 (also known as the upstream O2 sensor).

P0053 is telling you that there is a problem with the Bank 1 Oxygen Sensor 1 (again, the upstream O2 sensor) Heater Circuit resistance.

Now what do these codes mean in a practical manner? Well, either there is a broken wire going to the upstream O2 sensor, or the heater which is incorporated into the O2 sensor is either shorted to ground, the heating element is broken, or the heating element has gained resistance.

So now you ask what should I do. Well, the first thing I would do is to verify that the wires going into the connector that plugs into the upstream O2 sensor (which is located in the exhaust manifold on the passenger side of the engine) are intact. If they are, then the odds are that the O2 sensor is bad. You could attempt to measure the resistance of the heating element (Pins D and C) using a Digital Multi Meter (DMM) set to the ohms mode. Also, you need to verify that 12 VDC is present at Pin D of the connector that plugs into the O2 Sensor's connector.

Considering that the O2 sensor is likely the original one installed at the factory, I would go ahead and replace it provided that the wires going to the O2 sensor are intact and there is 12 VDC present at Pin D (note red test lead of the DMM goes to Pin D and the black test lead of the DMM goes to ground and the DMM is in DC volts mode.

Now if you have the tools and know how, you can change the O2 sensor yourself and save some $$$. You can save even more $$ if you order the new O2 sensor from rockauto.com! If you choose this route, I would recommend purchasing either a Denso or an ACDelco/GM Genuine O2 sensor. The part number for the Denso Upstream O2 sensor is 2344331 and it sells for $36.89. The part number for the ACDelco/GM Genuine O2 sensor is 213-3539 (or 12592591) and it sells for eek! It's out of stock, but it will cost more than the Denso sensor.

Good Luck!
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1. O2 sensors get lazy with age. Any O2 sensor older than 50K--80K miles is suspect ESPECIALLY if it's throwing a code. You're getting O2 sensor codes with an elderly O2 sensor, the smart money is on replacing the sensor because it's past it's expected life-span anyway. Fuel economy and driveability gains from a new sensor can--sometimes--offset the cost of the sensor.

2. O2 sensor sockets/wrenches are great for installing O2 sensors. They're often pretty lame at REMOVING them. Fairly often, I have to cut the sensor wire(s) and use a deep impact socket that does NOT have a split down the side.

3. The 6-popper exhaust manifold is known for extreme cracking. Good luck. Dorman sells "kits" with a new manifold, gasket, donut, heat shield, and hardware except for the bolts that hold the manifold to the cylinder head--which are available separately from Dorman. The heat shield is crap, the rest of the kit is pretty adequate except the manifold itself will be warped and the gasket surface isn't appropriately smooth. Take the brand-new manifold to an automotive machine shop to have it planed flat and smooth before you install it.

Note numerous cracks around the O2 sensor hole.
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Thank you for the codes. Regarding AutoZone, ask yourself this simple question - "What is AutoZone in business for?" Unfortunately, many of the employees at AutoZone, Advance Auto Parts, O'Reilly Auto Parts, etc. really know very little about working on automobiles and even less about the On-Board Diagnostics (OBD II) systems. You did the right thing - you purchased your own OBDII code reader! Congrats!

OK, here goes the explanation of the codes, a little tutorial and what you need to do to proceed.

P0030 is telling you that there is a problem with the Heater Control Circuit which is located in the Bank 1 Oxygen Sensor 1 (also known as the upstream O2 sensor).

P0053 is telling you that there is a problem with the Bank 1 Oxygen Sensor 1 (again, the upstream O2 sensor) Heater Circuit resistance.

Now what do these codes mean in a practical manner? Well, either there is a broken wire going to the upstream O2 sensor, or the heater which is incorporated into the O2 sensor is either shorted to ground, the heating element is broken, or the heating element has gained resistance.

So now you ask what should I do. Well, the first thing I would do is to verify that the wires going into the connector that plugs into the upstream O2 sensor (which is located in the exhaust manifold on the passenger side of the engine) are intact. If they are, then the odds are that the O2 sensor is bad. You could attempt to measure the resistance of the heating element (Pins D and C) using a Digital Multi Meter (DMM) set to the ohms mode. Also, you need to verify that 12 VDC is present at Pin D of the connector that plugs into the O2 Sensor's connector.

Considering that the O2 sensor is likely the original one installed at the factory, I would go ahead and replace it provided that the wires going to the O2 sensor are intact and there is 12 VDC present at Pin D (note red test lead of the DMM goes to Pin D and the black test lead of the DMM goes to ground and the DMM is in DC volts mode.

Now if you have the tools and know how, you can change the O2 sensor yourself and save some $$$. You can save even more $$ if you order the new O2 sensor from rockauto.com! If you choose this route, I would recommend purchasing either a Denso or an ACDelco/GM Genuine O2 sensor. The part number for the Denso Upstream O2 sensor is 2344331 and it sells for $36.89. The part number for the ACDelco/GM Genuine O2 sensor is 213-3539 (or 12592591) and it sells for eek! It's out of stock, but it will cost more than the Denso sensor.

Good Luck!
Thanks chem_man!! As always, fantastic advice on how to proceed. I'll be fixing her this weekend. I'll let you know how I make out 馃憤
Do they need to be replaced in pairs? I've heard mixed things and am assuming yes. Just want to make sure before I order a GM Genuine replacement for both.
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metalmike - if you do not know the history of the O2 sensors, I would go ahead and replace both of them due to age and mileage.

As an aside, whenever I have replaced an O2 sensor, I have always used Denso O2 sensors with great luck.

Good Luck!
Good info here. Thanks to all contributors. Thinking I might add a set of O2 sensors to my list to see if it improves my crappy 13mpg. No codes currently and hopefully none afterwards as well!
Good info here. Thanks to all contributors. Thinking I might add a set of O2 sensors to my list to see if it improves my crappy 13mpg. No codes currently and hopefully none afterwards as well!
Thank you. Adding this to the summer project list.
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