[birry335]

Hey everyone, I've been having some intermittent coolant high temp alarms. After roughly 35-45 minutes of driving, the yellow alarm will appear, and the red alarm about 10 seconds later. It will go into turtle mode. I can pull over, and turn off my engine and restart, and the alarm will clear for another 30 minutes. The first time it happened, there was a small amount of coolant that leaked by the reservoir cap.
If anyone has any input, it would be greatly appreciated.
Thanks!

[JETmn]

Water pump is shot. Happened to me 4k miles ago, exactly the same.

[Andrewe92]

it's almost common knowledge around here n55/n54 that when you get yellow warning than the red over heating warning.. it comes down to the water pump/ thermostat ... I'm at 33k miles and on the highway going 70 cruise control with air condition on I got the yellow than red warning light.. when it happened I knew instantly it was the water pump, thankfully my warranty only went up few months ago so bmw helped out with the cost.. only paid 250 for new water pump and thermostat including labor.. at any rate, do yourself a favor and get it taken care of asap because the coolant is meant to keep some very important engine components cooler.. so when you are driving around with a bad water pump you are really taking a risk of causing major damage, also note when your rad fan kicks up it is trying to make up for the high coolant temp by increasing air flow through the radiator. update us when you replace the water pump which im positive is the issue in your case

[birry335]

Ok, I'll get it taken care of asap. Thanks a lot!

[norsairius]

It's upsetting that even later model year E9x 335s need to worry about this. You'd think BMW would have gotten their crap together. I'm really curious what's causing all these failures.

[9 amini]

had the same thing happen to me at like 22k miles. water pump

[birry335]

So... I brought it to the dealership today, and they cannot positively identify it as the water pump or thermostat. Apparently, they were not getting the code for the motor failure, as they should. They said it could be a fault in the wiring, or something similar. I was in a recent collision, and the advisor said it could also be from that.
Any thoughts?

[Andrewe92]

Originally Posted by birry335

So... I brought it to the dealership today, and they cannot positively identify it as the water pump or thermostat. Apparently, they were not getting the code for the motor failure, as they should. They said it could be a fault in the wiring, or something similar. I was in a recent collision, and the advisor said it could also be from that.
Any thoughts?

Interesting , I personally don't think it was from a recent accident like your s.a is suggesting. Have you gotten warning recently again ? Is your radiator fan kicking up rpm? Are you checking the actual coolant temp? Possibly a coolant leak?? A good shop including a good bmw dealer should be able to get to the bottom of the problem if I were you I would push your s.a to figure it out especially if you are under warranty. Just my two cents

[Andrewe92]

Originally Posted by norsairius

It's upsetting that even later model year E9x 335s need to worry about this. You'd think BMW would have gotten their crap together. I'm really curious what's causing all these failures.

I'm not a guru in this topic by any means but by nature water pumps in general are kinda prone to failure because of the tough job it has to perform. I mean we are talking about very hot coolant running through the pump than cooling off and heating up day in and day out. I've seen the inside of different types of water pumps and by nature they fail sometimes sooner than the makers would like it too

[birry335]

Great news... I took my car back to the dealer, after the problem became more frequent, and they did determine it was the water pump and thermo. Since I am only at 53k miles, they are replacing everything 100% free of charge. Also, since the Vanos bolt recall is officially out, and no longer pending, they are replacing the bolts as well