[f10Ben]

Hi everyone,

I drive a 2011 535xi with around 90k miles. I recently did OFHG and Valve cover around 800-1k miles ago.

Today I driving and I got a strange sound from the engine bay it was like a fan sound very muffled but loud when I opened the bay. I received the yellow alert saying temp hot drive moderate so I stopped pulled over added some coolant and then started driving then I started again and received a yellow then red saying pull over and was in limp mode. When I popped the hood the fan was going crazy I could feel air flying in.This was all within a 15 min drive.


Does anyone know what this could be? Let me know if any more details are needed. I am not experienced and would love any advice. Thank you all!!!!

Also I have a video of the sound but I’m not sure how to upload it if anyone has advice there.

[Surly73]

Probably tstat or pump failure. Pull codes.

[f10Ben]

Originally Posted by Surly73

Probably tstat or pump failure. Pull codes.

I wasn’t able to pull codes because no check engine light. You are definitely right. I looked on FCP Euro and I couldn’t find a kit for what I need. Would you say I need both?

[ChiltiCoatl89]

FCP Euro does have a kit that includes a WP and a Tstat with some Coolant. You can also do a water pump test, This is a very common and known issue on all 5ers, Plenty of info here on the Forum, be sure to check for leaks and also check your Coolant Expansion tank and all hoses.

[Surly73]

Originally Posted by f10Ben

I wasn’t able to pull codes because no check engine light. You are definitely right. I looked on FCP Euro and I couldn’t find a kit for what I need. Would you say I need both?

That's not how that works. Any proper BMW-aware scan tool or app can pull codes at any time, and will usually have some logged even with no CEL. If you "can't pull codes because no check engine light" you are not using the correct tool.

I don't know if you need both, but if you're replacing one I would replace the other. They're right beside each other, both require draining coolant and making a mess, and either could be responsible for overheating.