O2 sensor help!

[GenesisGuy70]

Hi all,

So I think it's time to replace the O2 sensors on the Taurus (2010, SEL, 131,000). I keep getting CEL's for basically all of them. However, when I went to order them this morning I pulled up a schematic from Ford and I could only find 2 in the diagram, so that's all I ordered. But I just popped the hood I think I seen 3 and I think 4. But I'm not sure they were actually O2 sensors.

So basically, how many does this darn thing have? Here is what I ordered this morning from RockAuto:

ACDELCO 2134613 (213-4613) Oxygen (O2) Sensor $ 94.79 $ 0.00 1 $ 94.79
DENSO 2344610 (234-4610) Oxygen (O2) Sensor $ 24.79 $ 0.00 1 $ 24.79

1 upstream, 1 downstream.

Is that it or am I missing something? Yes I know, how dumb of me to not look under the hood FIRST.

Thanks

 

[bdcardinal]

Give me the last 8 of your VIN, either here or in a PM and I can tell you what ones go where.

 

[GenesisGuy70]

AG154368

Thanks @bdcardnial!

 

[bdcardinal]

The 2 air/fuel O2 sensors are 8F9Z-9F472-A and are mounted in the exhaust manifolds. The 2 catalyst monitor O2 sensors are 5F9Z-9G444-AB and are mounted in the catalytic converter bodies that are bolted to the exhaust manifolds.

 

[GenesisGuy70]

Thank you!

I did order one of each of those, I just need another set. Well that just made this a twice as expensive job!

 

[GenesisGuy70]

Well I was willing to spend $130 to do this job, $260 is quite another. I think I'll just forget changing them and just keep resetting the CEL's. That's free and takes 4 secs.

 

[Wolf359]

Just replace the upstream sensors. Also exactly what codes are you getting? Some codes point to O2 but sometimes it's a vacuum leak that the O2 sensors can't handle. The upstream sensors are the ones that switch the most, the downstream ones don't do too much switching and when they're bad, the cats are shot. I had replaced the upstreams on my 2001 Taurus, but never did the downstream and they were still good at 200k+. I'd replace them before you burn out your cats.

 

[GenesisGuy70]

Codes:

P0150, Bank 2, Sensor 1
P0130, Bank 1, Sensor 1

Not sure which those correlate to

 

[DerbyDave]

It would be very odd to have both upstream sensors fail at the same time. I think you are chasing a different problem. Possible causes for the codes you gave are below. I would look at the last 4. As a previous poster said a vacuum leak would be high on the list of likely causes.

- Faulty Front Heated Oxygen Sensor Bank 1
- Front Heated Oxygen Sensor Bank 1 harness is open or shorted
- Front Heated Oxygen Sensor Bank 1 circuit poor electrical connection
- Inappropriate fuel pressure
- Faulty fuel injectors
- Intake air leaks may be faulty
- Exhaust gas leaks

 

[LeakySeals]

Yes both failing same time would be unlikely. I would replace the IMG and see what happens. Cheap fix but makes a big difference.

 

[bdcardinal]

Codes are for both upstream O2 sensors. Very unlikely that is the cause. I would look for a vacuum leak or something allowing air in after the MAF. Even the intake plenum o-rings are pretty common.

 

[440Magnum]

I agree- its not an O2 sensor problem or both of the upstream seonsors wouldn't throw codes simultaneously. Well, its possible, but highly unlikely. Much more likely that its something common to both of them- like fuel starvation (low fuel pressure, failing fuel pump, clogged fuel filter), leaky injector causing a rich condition, an intake air leak causing a lean mixture, etc. I don't know if the engine management on that car uses mass air flow or speed/density, but mass-airflow systems are very easily skewed lean by leaks downstream of the MAF sensor.

 

[DerbyDave]

You can probably rule out a leaky injector since it is not common to both banks

 

[Wolf359]

Whatever it is, you should fix it soon, just clearing the code will eventually lead to cooked catalytic converters and if you thought $260 was a lot, wait til you see the prices of a few cats, you have to buy them new, junkyards can't sell them.

 

[Trav]

Post your fuel trim values. As others have said the chances of 2 failing at the same time barring an electrical short of some sort are about the same as winning the lottery.
Proper diagnosing is key to a good and usually less expensive repair than randomly replacing parts based on a ecm code.

 

[asand1]

The senors will have a heating circuit fuse. Find it and check it.