N62TU oil level sensor always showing full

[LightlyToasted]

'07 X5, 4.8i with N62TU engine.

iDrive oil level always shows full, but dipstick tells another story. Like all N62 engines, mine leaks oil, and I need to top it off once or twice between oil changes.

I've found a few references to running diagnostics on the sensor before replacing it. Haven't yet got my laptop set up for coding the E70, but will shortly. Before I buy a new sensor, do these sensors typically fail and require replacement, or can there be other problems?

[Thecastle]

ITs not unheard of for the sensors to fail, I've seen threads on the topic. Its a fairly cheap part like in the $30 range, so it might be worth trying to just replace and see.

have you been taking the oil level measurement always on level ground and after the engine has been stopped for at least 5 minutes? The reason being is that the engine can show low on the dipstick but still be at the proper level.

My 4.8i leaked a little and burned a little (bad valve stem seals) but it wasn't significant enough that I had to add more than 1 qt every 5K miles or so. My oil level sensor would show the level gradually falling over time but take about 10 minutes of driving before it would register a change in level.

[LightlyToasted]

IIRC, the oil level sensor on the N62 is an oil level and condition (pH) sensor, which is in the neighborhood of $300 OEM, or $170 aftermarket. Level only sensors for other models were a lot cheaper, around $25 on Amazon. If you can find an N62 sensor cheaper, please let me know.

I always check my oil level on a cold engine with the vehicle parked in my garage (level enough). I'll typically add at least 1L over 10K km, so it definitely does consume some. Doesn't matter what the dipstick says, iDrive always shows full. I'd like to have some confidence in iDrive, given this engine's history of developing leaks.

I'll probably just go ahead and replace it. My default for most things on a 10 year old vehicle. It will also prompt me to get INPA set up for the E70.

[Thecastle]

$178 from BMW of Des Moines... Yeah its fairly expensive. ITs really not a big deal to have it fail full and just check the dip stick? I tend to go the other way and go cheaper on older cars. Like my X5 4.8i had its rear power hatch struts fail, so I put in the old fashioned manual ones for $45. Same with the sunroof venting, I just disabled the second one from venting so it would close reliably.

https://www.bmwoemautoparts.com/oem-...AaAjlwEALw_wcB

[LightlyToasted]

Is it a big deal for the iDrive to always show full? No, since I already know of it being a false reading and don't rely on it, and I'm back to relying on a dipstick like in almost every other vehicle I've owned.

That is, until it is a big deal. If a leak is slow enough, I'll catch it via semi-regular dipstick checks. If it's really rapid, as was the oil cooler thermostat gasket leak that I fixed earlier this year, my first clue might be an oil pressure warning. Develop one of those on a road trip, where you don't have a garage floor to notice oil drops on, and you're cooked. Would be nice to get an oil level warning prior to that.

To each his own, but I'd rather have a sensor that works. Was just inquiring about the likelihood that it's actually the sensor and not something else, but I think I'll just take a chance and replace the sensor.

[LightlyToasted]

Changed the oil today, and replaced the oil level sensor. I initially intentionally underfilled the oil by 1L (low point on dipstick), and took it out for a test drive. iDrive showed oil level at maximum. So it appears that the oil level sensor may not have been faulty.

I'm going to work to get INPA set up, and run a diagnostic on the sensor. I read somewhere that it is also possible to clear the long term oil level value. I'll report back when I know more.

[ingenieur]

Or drive it longer for the long term measurement to complete - usually 20 - 30 minutes w/o sportive driving.

[LightlyToasted]

Originally Posted by ingenieur

Or drive it longer for the long term measurement to complete - usually 20 - 30 minutes w/o sportive driving.

Will do, and will report back. My test drive was only 10 minutes or so. Good excuse to take an extra long errand run today :-)

[LightlyToasted]

Oil is at 1/2 mark on dipstick. Went for a 30 min drive; iDrive still shows oil level at max.

I'll run an INPA diagnostic when I get it set up.

[robnitro]

Do you know if your dipstick tube is fully secure? It might have slid out perhaps, reading low when it's full?

On your oil change to 1l low for testing do you recall how much oil you put in and what the capacity normally is?

Just wonder if the dipstick could be wrong, though I trust that more than the sensor, you never know!

Also try checking the oil with the car facing down hill, on my 35d, it reads almost 1/3 lower at that angle, which might help you see if the sensor reads lower.