Problem with 35d x5 p0112 and p0675

[2011diesel]

Hey guys, I've been having a check engine light on my x5 for awhile now, it's showing 2 codes which are p0112 intake air temperature sensor and p0675 cylinder 5 glow plug curcuit. Now the x5 runs fine, nothing noticeable. I did just replaced the intake air temperature sensor, and replaced the air filter (it was dirty) and cleaned the MAF sensor, and both codes are still there. On Bosch code reader says they are permanent, trying to erase them, and the check engine light turns off, until the car is restarted and it's back on. I did a lot of research already, before I posted this, and no luck. Please let me know where to look, I can't afford to pay $190 to BMW for diagnostics just yet, but will have to if nothing else can be done. Also to note, I took the car on a long trip from WA to CA, and my mpg was 25. I'm not sure if that's normal or if it's suppose to be more. The car has power, I didn't notice any power reduction.

[daytonatrbo]

Originally Posted by 2011diesel

Hey guys, I've been having a check engine light on my x5 for awhile now, it's showing 2 codes which are p0112 intake air temperature sensor and p0675 cylinder 5 glow plug curcuit. Now the x5 runs fine, nothing noticeable. I did just replaced the intake air temperature sensor, and replaced the air filter (it was dirty) and cleaned the MAF sensor, and both codes are still there. On Bosch code reader says they are permanent, trying to erase them, and the check engine light turns off, until the car is restarted and it's back on. I did a lot of research already, before I posted this, and no luck. Please let me know where to look, I can't afford to pay $190 to BMW for diagnostics just yet, but will have to if nothing else can be done. Also to note, I took the car on a long trip from WA to CA, and my mpg was 25. I'm not sure if that's normal or if it's suppose to be more. The car has power, I didn't notice any power reduction.

I'm starting to sound like a broken record here, but check out your engine coolant temp when driving. (Menu 7) It seems like most of the glow plug/glow module issues I've read about turned out to be due to low coolant temp due to a bad thermostat.

[2011diesel]

Originally Posted by daytonatrbo

I'm starting to sound like a broken record here, but check out your engine coolant temp when driving. (Menu 7) It seems like most of the glow plug/glow module issues I've read about turned out to be due to low coolant temp due to a bad thermostat.

I was actually checking that today, and mine is usually around 78-83 C when driving 60-65 mph. Didn't see it go higher than 83 C. When downshifting manually it goes down to 72 C. Are these normal temps?

[seattle]

Originally Posted by 2011diesel

I was actually checking that today, and mine is usually around 78-83 C when driving 60-65 mph. Didn't see it go higher than 83 C. When downshifting manually it goes down to 72 C. Are these normal temps?

Nope, not normal.
After putting new thermostat, temp in mine hovers around 90C, occasionally going to toasty 95c on uphill or something.

[2011diesel]

Originally Posted by seattle

Nope, not normal.
After putting new thermostat, temp in mine hovers around 90C, occasionally going to toasty 95c on uphill or something.

Thanks for the input, I was planning on replacing the thermostat. But it doesn't fix the air intake temp sensor, it's what concerns me the most. Could it be that it needs to be reset with BMW computer and not generic reader?

[daytonatrbo]

Originally Posted by seattle

Nope, not normal.
After putting new thermostat, temp in mine hovers around 90C, occasionally going to toasty 95c on uphill or something.

Ditto here. Mine now hits 88 easily and wants to stay around 90-92

Originally Posted by 2011diesel

Thanks for the input, I was planning on replacing the thermostat. But it doesn't fix the air intake temp sensor, it's what concerns me the most. Could it be that it needs to be reset with BMW computer and not generic reader?

I would try a better reader. I would expect the code to at least go away briefly before coming back.

[2011diesel]

Originally Posted by seattle

Nope, not normal.
After putting new thermostat, temp in mine hovers around 90C, occasionally going to toasty 95c on uphill or something.

Is it hard to replace the thermostat yourself?

[2011diesel]

Originally Posted by daytonatrbo

Ditto here. Mine now hits 88 easily and wants to stay around 90-92



I would try a better reader. I would expect the code to at least go away briefly before coming back.

So that would mean I have to take it to a dealer?

[daytonatrbo]

Originally Posted by 2011diesel

Is it hard to replace the thermostat yourself?

The hardest part is getting the cooling fan out past the charge pipe. The rest of the job is pretty typical.

Probably wise to pick up a few of the smaller coolant lines, like for the EGR cooler. I gambled and didn't replace any thing other than the water pump and T-stat. So far, no leaks. My water pump was just starting to get a little play in it.

[daytonatrbo]

Originally Posted by 2011diesel

So that would mean I have to take it to a dealer?

I have INPA on my laptop and an $18 cable. Basically the same as the dealer used to use.