Overheating Issue

[Usmc1028]

Originally Posted by racingbmwm3

Have an infrared heat gun to do spot temperature measurements? You'll have to remove the electric fan to do this, but take spot measurements all over the radiator to see if it has hot and cold spots. should be almost uniform in temperature. If you have colder spots in the middle or scattered around it, then its the radiator.

I dont have a infrared heat gun atm, there not expensive, but im just going to swap it out to see if it cures the problem.

[Usmc1028]

Well at least i know its not my temp sensor. Ill swap out radiator with my dads x5 see if this fixes anything. If not i may have a big prob here. So yall dont thing having any a/c pressure in the lines is causing it to overheat.

[upallnight]

Originally Posted by Usmc1028

Well at least i know its not my temp sensor. Ill swap out radiator with my dads x5 see if this fixes anything. If not i may have a big prob here. So yall dont thing having any a/c pressure in the lines is causing it to overheat.

Nope.

Did you have the manual or Automatic control? Heater control should be at full max heat when you are doing the bleeding.

[tmv]

Originally Posted by upallnight

Nope.

Did you have the manual or Automatic control? Heater control should be at full max heat when you are doing the bleeding.

Just to clarify: as my understanding when bleeding to cooling system, heater control to maximum (90 degree) and fan control at minimum (1 bar), to get the latent heat pump running.

[Usmc1028]

Originally Posted by tmv

Just to clarify: as my understanding when bleeding to cooling system, heater control to maximum (90 degree) and fan control at minimum (1 bar), to get the latent heat pump running.

Yes, this has always worked for me in all 5 of my bmw. 1999 328i, 2001 x5 3.0, 2006 x5 3.0, 2006 530i, and well i aint don't it on the 2013 320i yet, but i'm sure its the same. All of these are stilling running fine till this day, upset the 2006 x5 3.0, but before the motor swap it ran fine when i did the cooling system.

[Doru]

I had a similar experience, but with the 4.4 (v8). Different engines, but similar result.
The culprit in my case was the double temperature switch, having one element gone bust, enough to have the t-stat closed when reaching operating temperature. The only way to "cool" down the engine was with A/C on. It was tough to find the culprit, but with INPA/GT1 it was done.
In your case, you have also a dual temp switch, located at the back of the engine - look here - item #3. If one element goes gangbusters, it will NOT read the high (operating) temperature, but a high and a cold one, assuming the engine is still warming up, and not giving the signal to open up the t-stat.
One way to check this, is take out the dual temp switch and measure it with a multimeter. I have posted this (for the 4.4) in this forum. If you search for it, you will find it, and I believe the values that should read are also posted. If I failed to post these values, then with the multimeter read the values for both sensors inside the dual switch - they should be similar. If one is bad, you will have 2 different values.

[Usmc1028]

Originally Posted by Doru

I had a similar experience, but with the 4.4 (v8). Different engines, but similar result.
The culprit in my case was the double temperature switch, having one element gone bust, enough to have the t-stat closed when reaching operating temperature. The only way to "cool" down the engine was with A/C on. It was tough to find the culprit, but with INPA/GT1 it was done.
In your case, you have also a dual temp switch, located at the back of the engine - look here - item #3. If one element goes gangbusters, it will NOT read the high (operating) temperature, but a high and a cold one, assuming the engine is still warming up, and not giving the signal to open up the t-stat.
One way to check this, is take out the dual temp switch and measure it with a multimeter. I have posted this (for the 4.4) in this forum. If you search for it, you will find it, and I believe the values that should read are also posted. If I failed to post these values, then with the multimeter read the values for both sensors inside the dual switch - they should be similar. If one is bad, you will have 2 different values.

Of course the switch would be under the intank lol! Thanks for the information ill deff check this out if switching the rad, t-stat and water valve dont work.

[racingbmwm3]

AC system is completely separate from the heating system. And not having/using AC would make it run cooler.

[Usmc1028]

Originally Posted by racingbmwm3

AC system is completely separate from the heating system. And not having/using AC would make it run cooler.

Looking at RealOEM it looks like one of the hard lines is connected to the heater core but i could be looking at it wrong.

[racingbmwm3]

Yes and Yes and this works for those cars without the heat pump also. It's to make sure air doesn't get trapped inside the heater core.