Overheating warning but car isn't actually overheating?

[Odin2347]

My radiator fan seems to be going nuts all the time and after driving for 10-15 min I get a temperature warning and the car goes into extreme limp mode. Restarting the car makes this goes away for another random period of time...even hours. There are no signs of actual overheating..no burnt smell no steam under the hood coolant level is fine and not boiling. No idea what this could be, maybe coolant temp sensor?

[cheshirecat79]

Your water pump is dying. There's a ton of information about it on here. Stop driving it as you're going to end up getting stranded on the side of the road unless you get it serviced.

[Odin2347]

Originally Posted by cheshirecat79

Your water pump is dying. There's a ton of information about it on here. Stop driving it as you're going to end up getting stranded on the side of the road unless you get it serviced.

hmm wouldn't I have symptoms of overheating then? temp warning comes on and a restart of the car makes it go away

[milocher]

Originally Posted by Odin2347

hmm wouldn't I have symptoms of overheating then? temp warning comes on and a restart of the car makes it go away

Had this happen to me. No it won't actually overheat, the vehicle is detecting a constant increase in engine temp despite being at 100% cooling capacity. If the discrepancy is too high, it will do exactly what you've had happen.

Restarting the car can make it go away since the engine itself hasn't overheated, but once the car cranks back up to 100% and notices temperature continuing to increase, it'll drop back into limp. In essence this is a fail safe built in order to prevent any chance of even momentary overheating.

[dji]

Change your water pump and thermostat at the same time asap. Dont drive the car anymore you will have the red sign and the car will stop, after that towing time. Been there done that, I was not aware of this.

[Odin2347]

Originally Posted by dji

Change your water pump and thermostat at the same time asap. Dont drive the car anymore you will have the red sign and the car will stop, after that towing time. Been there done that, I was not aware of this.

I get the red sign every time I drive and then an immediate restart of the car makes it go away. Coolant temp seems normal in logs. I'm not driving it til the coolant temp sensor I ordered comes in. If it's not that then it's the pump

[Dackelone]

Have you checked for codes? Sounds like a classic waterpump/thermostat failure to me.

[Odin2347]

Originally Posted by Dackelone

Have you checked for codes? Sounds like a classic waterpump/thermostat failure to me.

no BT cable :/

[Dackelone]

Originally Posted by Odin2347

no BT cable :/

You might call BMW Assist. At least over here in Germany... they will come out(and read your codes) look your car over. All work is free for the first 30 min. After that you have to pay IF you have an older car. But I would call and ask. Whats the worse they could say?

[RX-BMW]

Did you figure out what it was?

I had this happen to me today

[marc@x-ph.com]

Originally Posted by RX-BMW

Did you figure out what it was?

I had this happen to me today

It is more than likely the water pump. our cars are notorious for water pump issues. Sometimes the pump is just broken, other times the piping literally broke and the pump is losing coolant (this is easy to check)

[Odin2347]

It was the pump...

[twin fed]

Definitely the water pump. Your exact same situation just happened to me.

[marc@x-ph.com]

Originally Posted by twin fed

Definitely the water pump. Your exact same situation just happened to me.

Happened to all of us at some point hehe.

I changed two on my last car. First pump failed, second broke.

[RX-BMW]

So I had to uninstall COBB before I took the car in (COBB AP showed tons of codes regarding water pump and e-fan failure). Now that it's uninstalled it cleared all the codes and now reads none....I really hope the dealer can replicate the problem while test driving it. Sigh

[awns729]

Curious, what mileage are you at?

[RX-BMW]

Me i'm at 55,000

[help me]

100% water pump failure
I went through this for over a month trying to diagnose and found that water pump would just stop working them engine go into limp mode and simply by turning car off then straight back on would kick start pump again and would be ok again for anything up to a couple of days without any problems

[Odin2347]

Originally Posted by help me

100% water pump failure
I went through this for over a month trying to diagnose and found that water pump would just stop working them engine go into limp mode and simply by turning car off then straight back on would kick start pump again and would be ok again for anything up to a couple of days without any problems

yep this basically what was happening. 55k miles on the car at the time of failure

[RX-BMW]

It was the water pump, they said 'the codes were still there' and fixed it. Car runs great now

[miiipilot]

I think this happened to me last night.

driving in heavy suburb traffic. Had my a/c on for defrost.

Got a yellow water temp light. I got a little nervous as it is 29 degrees out and I'm not in the best neighborhood.

Turned off the a/c, opened the windows and cranked the vent to high.

Noticed I had very little power in the engine, but no 1/2 power symbol.

THEN BING RED TEMP WARNING and then no power. Pulled over and turned the car off. Opened the hood. Couldn't smell anything really. I've had cars that have overheated and this wasn't it.

Called BMW Assist. They told me to call the Roadside Assistance.

Let it sit for a few minutes. Started right up, no warnings, nothing.

Drove it in some clean cold air...No problems.
Drove it to a friends and let it idle for 15 minutes...No problems.
Turned it off and let it sit for 6 hours and then drove home an hour...no problems
Drove to work this morning...no problems.

My GF and I were gonna take an overnight trip to Chicago last night, but the weather concern made us change our minds. That would've sucked.

Water pump/Thermo???

called SA this morning and waiting for a call back

'11 135 39,000miles

[Tom753]

I have been reading you guys, and experience the same limp situation so I guess I have to change the water pump. However, I and going to google the part and different options and I find like 3 different types of water pumps. Which is the one to change? the one with the pulley ?