Hi Everyone

I'm a longtime reader, first time poster of this site. I am always amazed at how much information is on this site! It must have saved me thousands of dollars being able to repair my XF myself. Thank you to everyone for their valuable knowledge on these awesome cars!

I have however hit a hurdle and I cannot find any information on the issue I am currently having with my XF.

It is running very rough, feels like it is missing. It is lacking power, feels like it is running at about 30% power and on 5 cylinders.

I put new platinum plugs in it about 3 months ago. I've checked the leads and they are fine.

I checked the secondary air intake pump and associated wiring and all seems good. I've also checked for vacuum leaks and disconnected hoses, they all seem fine.

It is an automatic, so when the car is stationary and in 'drive', I put one foot on the break and I touch the accelerator with my other foot it makes a rough sound, almost like a hole in the exhaust (even though there isnt one).

I connected my OBD reader and it is showing an error code P0151 which means O2 Sensor Circuit Low Voltage (Bank 2, Sensor 1).

I called the Chrysler stealership here in Australia and they wanted (wait for it) - $824 for a new O2 sensor!!! Criminals!!

My questions are:
1) Could this error code be related to anything other than the O2 sensor and its wiring, or could something like a blown intake manifold gasket (for example) be causing the issue?

2) Does anyone have the MB # for this part? They seem to be about 1000% cheaper here than the Chrysler stealerships.

Thank you very much in advance for any advice you can give.

Best regards

OZ XF.

 

I don't have the MB part #, but you should be able to pick up an O2 sensor from an auto parts shop or eBay.
NGK makes them or maybe Rob at Needswings can track one down for you.

http://www.ebay.com/itm/Mercedes-Benz-Oxygen-Sensor-BOSCH-0258006123-16123-NEW-OEM-MB-O2-/131513003104?fits=Make%3AChrysler%7CModel%3ACrossfire&hash=item1e9ec92c60&vxp=mtr
NTK Oxygen Sensors

 

is this a limited or srt? I had that code many times, just cleared it and kept going. have u dis connected the batt ( turn on the lights) to drain the capacitors in the system. jim

 

Thank you for your response Harbor and amx1397.

The car is a Limited. I did clear the codes a few times with my OBD tool, and also by removing the battery cable for a couple of hours whilst I was working on it but the code keeps coming back.

The code itself doesn't bother me too much, its more the car running rough that troubles me.

I wonder if there is nothing wrong with the O2 sensor and it is a issue related to something else? I find it strange that a search for P0151 only produces a few mentions on this forum. Usually there are dozens of pages with someone describing similar symptoms of their XF misbehaving.

Thanks for the link Harbor, I will look up those parts tomorrow when the shops open.

If there are anymore suggestions from anyone they would be greatly appreciated.

 

Is the same sensor used in front and rear ? If so might try switching. If not switch side to side and see if it follows the sensor.

ps a manifold leak can trigger an O2 failure.

 

Hi Padgett

I was wondering the same thing. Does anyone know if all the O2 sensors are the same?

 

Might also review page 9-192 & on in the '05 Service manual (downloadable).

POSSIBLE CAUSES

O2 SENSOR SIGNAL CIRCUIT OPEN
O2 SENSOR SIGNAL CIRCUIT SHORT TO GROUND
O2 SENSOR GROUND CIRCUIT OPEN
ENGINE EXHAUST LEAK
O2 SENSOR
POWERTRAIN CONTROL MODULE

You can also monitor the sensor reading in real time with Torque Pro.

 

Alright, I'll add my progress on this post for future reference for anyone else with this same problem.

All O2 sensors are the same (same part #).

Likely issue is faulty wiring to the sensors, a leak in the exhaust or faulty O2 sensor.

In Australia the O2 sensors are extremely expensive, Mercedes just quoted me over $1000. I'm not joking!!

If you can wait for the part ex US, Ebay is the way to go (as Harbor pointed out above). If not, and you are in Australia, it pays to shop around. The cheapest price I can get here so far is $175.00 for an NGK sensor.

Before shelling out the cash I will get under the car and have a look at wiring and exhaust.

Will let you know how I go.

 

If you do have a faulty sensor, you can also check RockAuto. They have a large selection of O2 sensors at low prices and they ship to OZ.

https://www.customerlobby.com/review...review/344511/

 

I would check out the wiring closely while up in the air. If all four are the same next I'd switch front and rear (rears do not do much, are really to verify that CC is working by staying neutral.

Can monitor all four sensors on a smart phone, helps to spot whether the problem is the sensor or wiring.

 

Problem Solved!

As it turns out; there was a hairline fracture in the left cat!!

I took it in to Exhaust Tourqe around the corner and they put a smoke machine in the 02 sensor ports. It was like a shady 70's disco!

The guys welded the cat up and its now as good as new.

Thanks to all you folks for your input!

I hope this thread helps others out in the future!

Best!

OZ XF!!

 

BTW - It cost me $180 for 3 hours work on the car, not too bad in Oz!!

 

Good to know, thanks.

 

"O2 Sensor Circuit Low Voltage (Bank 2, Sensor 1)." Interesting. I would have expected a crack in the CC to affect the downstream O2 and not the upstream.

Will need to remember that.

 

Thanks for posting the solution. So many ask for advice and then never let everyone know the outcome. You may have saved others a lot of headaches and grief.