Oxygen Sensor or ECU?

slay2k · 01-30-2018, 08:07 PM

Hey boys, need some help.

Got a check-engine light, read code in Torque app, showing as:

P0050 - Powertrain - HO2S Heater Control Circuit (Bank 2 Sensor 1)

Ordered one of these from Amazon: Bosch Original Equipment 17098 Oxygen Sensor

Which is for Bank 1, as it was a) half the price of Bank 2 and b) I've read many comments from people who successfully installed it in Bank 2, noting simply that aside from the identical connector & sensor the cable is a bit longer.

So I had my local BMW-specialist shop install it. Unfortunately, the car still throws the same code and he now believes the ECU may be bad.

So: how likely is it that the issue is the new sensor (or the bank 1 vs 2 issue) throwing the exact same code. Or something to do w/ the ECU? How likely is the ECU to fail w/ something like this?

Don't want to keep buying sensors to investigate. How would you boys proceed?

RocketSurgeon · 01-30-2018, 08:59 PM

I suspect you got a knockoff sensor. I got a knockoff and got the exact same error code.
Perhaps swap your sensors and see if the code follows the sensor.

slay2k · 01-31-2018, 08:33 AM

Quote:

Originally Posted by RocketSurgeon

I suspect you got a knockoff sensor. I got a knockoff and got the exact same error code.
Perhaps swap your sensors and see if the code follows the sensor.

Gonna try that next, hopefully you're right and no rocket surgery will be required.

01-31-2018, 09:47 AM

Quote:

Originally Posted by RocketSurgeon

I suspect you got a knockoff sensor. I got a knockoff and got the exact same error code.

Which seller?

When I ordered mine, I made sure that Amazon was the seller...no issues.

slay2k · 01-31-2018, 10:50 AM

Quote:

Originally Posted by FCobra94

Which seller?

When I ordered mine, I made sure that Amazon was the seller...no issues.

Mine was "True Blue Parts", have yet to confirm sensor is bogus, should have that info shortly.

01-31-2018, 11:09 AM

Quote:

Originally Posted by slay2k

Mine was "True Blue Parts", have yet to confirm sensor is bogus, should have that info shortly.

Hmm...I've ordered many a brake pad from them (mostly Akebono units) with no issues. They're pretty well respected on Amazon and Ebay, I'd be surprised if they were selling non-authentic goods.

slay2k · 02-01-2018, 12:11 PM

UPDATE.

My shop put in a brand new sensor and got the same exact code, so it appears the sensor is not the problem. He said he can spend time diagnosing the wiring to make sure e.g. a mouse hadn't chewed on the wires, but that it could take up to 4 hours.

I told him to spend up to 2 hours on it and get back to me.

What do you guys think, should this be trivial to diagnose -- is there a way to confirm it's the ECU and not the wiring w/out spending up to 4 hours on it?

Cheers!

slay2k · 02-01-2018, 04:26 PM

2nd UPDATE.

He found a melted cable about 2 feet from the ECU running towards the sensor. The car runs fine w/ a brand new cable + Bank 2 sensor. Now I gotta decide whether to shell out another $150 for the brand new Bank 2 sensor or leave the replacement Bank 1 sensor (Bosch 17098) that is supposed to be usable in both banks.

langsbr · 02-01-2018, 07:50 PM

The replacement bank 1 sensor is fine. It's just got a longer cord.

slay2k · 02-01-2018, 08:03 PM

Quote:

Originally Posted by langsbr

The replacement bank 1 sensor is fine. It's just got a longer cord.

Yeah, that's what I told him to put back in. Should pick up the car tomorrow. Not sure why the wire melted, maybe a previous mechanic messed things up w/ insulation while changing the valve cover gaskets, etc.

techwhiz · 02-02-2018, 06:14 PM

Replace the sensors in pairs just like bulbs.

slay2k · 02-02-2018, 07:03 PM

Too late for that, but you're the first one I've seen advocating that.

01-30-2018, 08:07 PM	#1
slay2k Private First Class 20 Rep 123 Posts Drives: 2007 335i Join Date: Sep 2014 Location: United States iTrader: (0)	Oxygen Sensor or ECU? Hey boys, need some help. Got a check-engine light, read code in Torque app, showing as: P0050 - Powertrain - HO2S Heater Control Circuit (Bank 2 Sensor 1) Ordered one of these from Amazon: Bosch Original Equipment 17098 Oxygen Sensor Which is for Bank 1, as it was a) half the price of Bank 2 and b) I've read many comments from people who successfully installed it in Bank 2, noting simply that aside from the identical connector & sensor the cable is a bit longer. So I had my local BMW-specialist shop install it. Unfortunately, the car still throws the same code and he now believes the ECU may be bad. So: how likely is it that the issue is the new sensor (or the bank 1 vs 2 issue) throwing the exact same code. Or something to do w/ the ECU? How likely is the ECU to fail w/ something like this? Don't want to keep buying sensors to investigate. How would you boys proceed?
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01-30-2018, 08:59 PM	#2
RocketSurgeon Lieutenant 264 Rep 459 Posts Drives: 2008 135i Manual, CBR650F Join Date: Jan 2017 Location: NC iTrader: (0)	I suspect you got a knockoff sensor. I got a knockoff and got the exact same error code. Perhaps swap your sensors and see if the code follows the sensor.
	Appreciate 1 Quote

02-01-2018, 12:11 PM	#7
slay2k Private First Class 20 Rep 123 Posts Drives: 2007 335i Join Date: Sep 2014 Location: United States iTrader: (0)	UPDATE. My shop put in a brand new sensor and got the same exact code, so it appears the sensor is not the problem. He said he can spend time diagnosing the wiring to make sure e.g. a mouse hadn't chewed on the wires, but that it could take up to 4 hours. I told him to spend up to 2 hours on it and get back to me. What do you guys think, should this be trivial to diagnose -- is there a way to confirm it's the ECU and not the wiring w/out spending up to 4 hours on it? Cheers!
	Appreciate 0 Quote

02-01-2018, 04:26 PM	#8
slay2k Private First Class 20 Rep 123 Posts Drives: 2007 335i Join Date: Sep 2014 Location: United States iTrader: (0)	2nd UPDATE. He found a melted cable about 2 feet from the ECU running towards the sensor. The car runs fine w/ a brand new cable + Bank 2 sensor. Now I gotta decide whether to shell out another $150 for the brand new Bank 2 sensor or leave the replacement Bank 1 sensor (Bosch 17098) that is supposed to be usable in both banks.
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02-01-2018, 07:50 PM	#9
langsbr First Lieutenant 234 Rep 317 Posts Drives: 335i Join Date: Aug 2013 Location: SC iTrader: (0)	The replacement bank 1 sensor is fine. It's just got a longer cord.
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02-02-2018, 06:14 PM	#11
techwhiz Colonel 453 Rep 2,973 Posts Drives: e90 335i Sedan - Arctic Join Date: Feb 2012 Location: Bay Area, Ca iTrader: (4)	Replace the sensors in pairs just like bulbs. __________________ Arctic Metallic\CF Splitters, Spoiler, Mirror Covers\LED Tails\LSD\Tinted\Coded\Apex Square SM10-19"\LED Angel Eyes\Gloss Black Grill\Integrated V1 & Galaxy Tab\M-Performance Brakes\Cobb Tuned\xHP Flash\Resonator Removed and -> is your friend.
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02-02-2018, 07:03 PM	#12
slay2k Private First Class 20 Rep 123 Posts Drives: 2007 335i Join Date: Sep 2014 Location: United States iTrader: (0)	Too late for that, but you're the first one I've seen advocating that.
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