[LRokosky]

Hello,

I have a 2007 328xi. Recently I have had problems with overheating. I looked up common causes for this and found the most probable to be the water pump or thermostat. However, I have no check engine lights or obd2 codes that would point to this. I looked for leaks, but didn't find any. Is it possible that the water pump or thermostat is bad but is not giving a check engine light?

Let me know if anyone has an idea

Thank you.

[RAZEx]

Hi LRokosky,

I drive a 2007 335i sedan. My car overheated today with no prior warning or symptom.

It overheated and showed a yellow warning, then a red overheat warning with reduced performance.

The car did not respond to the throttle and it moved like a slow turtle

The temprature reached 250°F and I turned it off right away.

I had it taken to a local expert - https://www.instagram.com/bavmotors/

Car was tested, water pump needs replacement.

[2one3E90]

I wonder what happen to cars without temp gauge

[Glene]

Originally Posted by LRokosky

Hello,

I have a 2007 328xi. Recently I have had problems with overheating. I looked up common causes for this and found the most probable to be the water pump or thermostat. However, I have no check engine lights or obd2 codes that would point to this. I looked for leaks, but didn't find any. Is it possible that the water pump or thermostat is bad but is not giving a check engine light?

Let me know if anyone has an idea

Thank you.

Key on -> 1 bar fan speed -> 84 degree temp and press/hold the gas pedal for 10 seconds. You can hear the water running if the water pump working.

[Bmw1939]

Originally Posted by 2one3E90

I wonder what happen to cars without temp gauge

The lack of a temp gauge is the dumbest idea ever. Of course you could use a bluetooth obd2 with bimmer tool lite and get it, but it just sucks.

[LRokosky]

I replaced my water pump and thermostat, and the car seems to be working fine now.

[hassmaschine]

Originally Posted by Bmw1939

The lack of a temp gauge is the dumbest idea ever. Of course you could use a bluetooth obd2 with bimmer tool lite and get it, but it just sucks.

Ehh. The DME will light the dash yellow or red if it actually gets too hot - it's pretty obvious, and that's only 5-10c hotter than the normal operating temp of the N52. It's not like you don't get any warning. And the normal operating temp varies so much, most people would just be confused by it.

The dumb thing is hiding the error codes for the pump. There's no CEL or SES for them - the only way to see them is with a BMW code reader.

[Luis561]

Originally Posted by Glene

Key on -> 1 bar fan speed -> 84 degree temp and press/hold the gas pedal for 10 seconds. You can hear the water running if the water pump working.

Definitely something I would do.

Try running the water pump with the engine off, if it doesn't run, there's your answer.

[jsunma]

Originally Posted by hassmaschine

And the normal operating temp varies so much, most people would just be confused by it.

Exactly. Most dashboard temp gauges don't reflect the actual coolant temp but rather just go to the middle position if the temp is within an acceptable range. Auto manufacturers years ago figured out that a variable temp gauge that read/reflected the actual coolant temperature was too confusing to operators. Which is why most also went for the "idiot light" (named that for a reason).

[marvinstockman]

LR, dumb question, but how did you know your car overheated.

I'd buy a cheap hand held infrared temp gauge, and get a feeling for normal underhood temps. If you have another vehicle, that would be a good place to start. All cars are about the same.

https://www.amazon.com/Infrared-Ther...s%2C171&sr=8-3

[MightyMouseTech]

Originally Posted by LRokosky

I replaced my water pump and thermostat, and the car seems to be working fine now.

Nice. Have seen several water pump failures without any faults.

[opjose]

My pump went out at 38k without any faults.

[N8N]

Originally Posted by jsunma

Exactly. Most dashboard temp gauges don't reflect the actual coolant temp but rather just go to the middle position if the temp is within an acceptable range. Auto manufacturers years ago figured out that a variable temp gauge that read/reflected the actual coolant temperature was too confusing to operators. Which is why most also went for the "idiot light" (named that for a reason).

I never did get the dash gauge on my '93 F-150 working properly. Yes, it was a gauge, but it was an idiot light with a needle if that makes any sense.