Common Problems to the BMW 3-series E90 Electric Water Pump

The E9x family of BMW 3-series cars (among others) came with an all new line of engines, beginning with N rather than the previous M and S model designations.  The 6 cylinder power plants have a few design features to make them more efficient in terms of power, fuel consumption, and emissions.  However, like most modern engines, there is a pretty glaring trouble point, the water pump.  These BMW’s utilize an electric water pump to allow computer controlling of coolant flow, rather than an engine speed dependent pump that saps drive power to run.

BMW water pump coolant kit

E90 electric water pumps tend to have a relatively short life span, and if yours fails you will end up on the side of the road (at best), with the threat of engine damage if the driver doesn’t take notice of an overheating engine (at worst).  There are three kits for these cars:

BMW Engine Water Pump And Thermostat Kit (N51 N52 N52N)

128i 2008-2011

325i 2006-2006

325xi 2006-2006

328i 2007-2011

328i xDrive 2009-2011

328xi 2007-2008

330i 2006-2006

330xi 2006-2006

525i 2006-2006

525xi 2006-2006

530i 2006-2007

530xi 2006-2007

X3 2007-2008

Z4 2006-2011

BMW Engine Water Pump and Thermostat Kit (N54)

+ BMW 1 Series M 2011-2011

+ BMW 135i 2008-2010

+ BMW 335i 2007-2010

+ BMW 335i xDrive 2009-2010

+ BMW 335is 2011-2011

+ BMW 335xi 2007-2008

+ BMW 535i 2008-2010

+ BMW 535i xDrive 2009-2010

+ BMW 535xi 2008-2008

BMW Engine Water Pump and Thermostat Kit (N55)

135i 2011-2013

135is 2013-2013

335i 2011-2013

335i xDrive 2011-2013

X1 2013-2015

X6 2011-2014

OES BMW N54/N55 Water Pump

The N54/N55 pumps in kit 100K10324 are OES VDO, same as Genuine BMW

You can tell the difference by simply looking at them.  The non-turbo cars get a full metal water pump where the turbocharged N54/N55 6 cylinders use a two part composite/aluminum pump.  If you are doing this job on an N51/N52 car, then you will notice the thermostat coming out is aluminum.  It seems that part is now only available in plastic composite.  The 135 and 335s came with a plastic composite thermostat from the factory.

Unfortunately, both of these pumps only last around 50-80k miles from the factory, and since they are a little tricky to replace, can cost a huge amount of money to do preemptively at the dealer.  eEuroparts carries a water pump kit that fits these 6 cylinder engines, and contains everything you need to keep your car reliable and happily on the road.

Pierburg Genuine BMW Electric Water Pump

The Pierburg part with the Genuine BMW Roundel. Save by buying OES.

The eEuro E90 Electric Water Pump Kits for N51, N52, N52 Engines

The kit contains everything you need to effectively change the water pump on your BMW at a much more effective price point.  The Pierberg water pump is the original equipment brand, at a significant savings over Genuine BMW.  The thermostat is a German made Wahler with integrated temperature sensor, another reputable company that supplies many car makers with their OEM parts.  We also carry the OES Behr unit if you like. This eEuro E90 Electric Water Pump Kit also features the water pump-to-thermostat hose, some high quality Genuine BMW hose clamps (trust me, you don’t want to use substandard hose clamps), and the very important E12 aluminum bolts that are specifically one-time-use.  Reusing the water pump bolts is a risky situation, especially since the location is tricky to get to if you snap one of them off.  German Made ROWE coolant and thermostat bolts are also included.

BMW Water Pump Bolts

Do not reuse these E12 Aluminum Bolts, always use new

The eEuro E90 Electric Water Pump Kits for N54/N55 Turbo Engines

These kits are basically the same, with a few subtle variations in part numbers.  The pumps are still OES, although BMW changed suppliers for the redesign, so our OES pumps are VDO rather than Pierberg.  There are subtle changes in the thermostat as well between the N54 kit (100K10365), and N55 kit (100K10324).  Also included are the hose, clamps, hardware, and ROWE coolant.

If you are mechanically inclined and are able to do basic mechanical tasks, this job is DIY capable.  It is a little finicky, so for the average DIYer, put aside a day for this job.  Savings on doing this yourself with the eEuro E90 electric water pump kit can go past $1000 depending on the shop.  With the car safely in the air, you will see the pump behind the sway bar  and power steering gear.  The first thing you want to do is disconnect the power steering cooling line from the bracket and pull it down out of the way.  Continue on by disconnecting the sway bar bushings from the subframe and let it swivel down.  Bungee it out of the way to keep from whacking your head on it repeatedly.

Installing the kit:

With access, you can go about removing the hose clamps to drain the coolant into a catch can.  The bolts are E12 inverted torx, and need to be replaced because they are one use only.  Keep in mind some of the hose clamps are quick connects and some are standard hose clamps.  You won’t be able to remove all the hoses before pulling the pump down because there is no access to the upper clamps with the pump in place.  Just remember the orientation of the pump as you remove it so you don’t twist the hose on re-installation.  The thermostat will be in view above the pump.  Take care to note the way the electrical connection clips work by looking at the new parts in your eEuro kit.   Here’s the coolant bleeding procedure:

Fill expansion tank with BMW coolant (50/50 mix), leave the cap off. With the key to the “on position” (no engine running), turn your heat all the way up with fan on the lowest speed without turning it off. Then hold gas pedal all the way to the floor (you’ll feel a click in the pedal) for about 10-15 seconds. You should hear the pump running, which will bleed air out of the system.  Remember to make sure your tank is full of antifreeze!  [thanks seb for that tip! -ed]

The water pump is tucked up underneath the car, behind the sway bar, power steering cooling line, subframe, and power steering rack (photo is from a UK car, so the steering rack will be reversed on US market vehicles)


22 thoughts on “Common Problems to the BMW 3-series E90 Electric Water Pump
    • Adam Goral

      Personally once you tick over 50k I would replace it. That is on the very beginning of when these are likely to start having problems, but I prefer to do preventative maintenance to avoid being stranded and having to pay more and potentially have problems due to local shop availability. I am a DIY’er though, so the thought of changing it on a nice day with some sodas is much better than getting stuck somewhere and having to pay joe shmo 6 blocks down to do it, and have to pay dealer prices on the parts.

  1. Dave

    I know the post is for an E90 but I just did this job as a dyi on a 2011 F10 535I xdrive M-Sport with the adjustable sway bars. There does not seem to be any info relating to this car and the job. Pump failed at 47,000 miles. After trying to follow 3 series and X1, X3 and X5 directions it was not possible on this vehicle. In the end the trick was to remove the upper support over the radiator and pull the fan out. After that the whole job could be completed with the large amount of space gained.

    • Adam Goral

      That’s great info, I will add a note to the post. Thanks Dave, hope this will help others too in this task. How about those active sway bars huh? There’s an article on this blog about the system kicking around, very fancy.

    • Charles J Gharamti

      Thanks for the tip- I have the same car and will be attempting the repair soon. Going to the the OFHG, belt, tensioner, and front left axle all at the same time.

      Did you have to disconnect the sway bar hydraulic lines to lower the sway bar enough to pull the water pump out? Did you remove the steering rack ?

  2. Seb

    These are fun! (Not!) If you have the SAV active sway bar system, free the pump and pull out from up top. Everything else from underneath. Use lots of extensions and wobblys/swivels. 7mm with a universal and 1/4″ extensions will do the trick on those damn hose clamps. If you have a 535xi gather your patience because their evil. Enjoy your coolant bath and scraped up arms!

  3. Seb

    Bleeding procedure:fill up expansion tank with BMW coolant (50/50 mix), leave the cap off. turn your heat all the way up with fan on the lowest speed. Then hold gas pedal all the way (you’ll feel a click in the pedal) about 10-15 seconds. Should hear the pump running and let it bleed it self remember to make sure your tank is full of coolant!

  4. suren

    MY E90 electric water pump is clicking but not pumping.The buttom pipe is cold while the top pipe is boiling hot .i have only replaced the top pipe and then is problem is evening boiling, not using this vehicle now.please help

    • Adam Goral

      Hi Suren, we offer a water pump or kit for your car to fix this problem. Tell me what your exact car is and I can advise you on a specific problem. Do not drive the car with a broken water pump.

  5. Keith

    Be aware that if you’ve experienced a pump failure, and then replaced the pump and STILL can’t get the new pump to start the bleed cycle, it is possible the original pump failure also blew the fuse. TIP: That water pump circuit fuse is located in your ECU wiring box under the hood (ECU box is on passenger side – remove the cabin air filter assembly, then unsnap and set aside the wiring harness and sensor(s) on the under-cowling, unbolt that cowling and lift it out of the way. ECU box is that largish cream colored box on the passenger side. Unsnap the 2 lid locks, then two more lid snaps and lift off the lid. See a big mess of wires. Buried down in there somewhere is yet another virtually inaccessible “unified locking fuse block” – the style varies with the year and model – but the fuse itself is a standard automotive blade style 30 amp fuse. On (at least) 2007 328i series, it resides in a small r3ctangukar black plastic removable fuse block sub-assembly. That sub assembly unplugs for bench access, but then has a tab-locked slide-off lid which further prevents direct access to the fuses. Unplug that block, take it to your bench. Flip it over, using a tiny pointed tool, press both release tabs and slide the cover off to access the fuses. Note: Do not break at it off!
    BMW engineers pay attention: Inaccessible fuses that cannot be easily discovered or accessed for replacement are almost criminal in their negligence of design! THE WHOLE POINT OF A FUSE IS TO PROVIDE A KNOWN POINT OF FAILURE IN A CIRCUIT – ONE THAT IS EASY TO ACCESS!

    Shame on you BMW.

  6. Maher

    Good evening guys,

    Who has any information about why does the water pump still in work even after removing the key for a long time until the battery goes off?

    Bmw e90 330i 2006

  7. Jacob

    I have a 328 I bmw that the original water pump went out, so I replaced it with new ones 3 times in a month. Seems that something keeps shorting the pump to not work then I’ll put a new one it would work for couple days then kill over again then repeat again with new one. Is there anyone no what might fry the electric in water pump

    • Adam Goral

      Hey Jacob, I have a few things for you to check. The first is, occasionally a bad engine mount will cause the wiring to get pinched, and can cause a fray and a short. The second is, see if you can get an electrical load off the input on the water pump to see if it’s really high or really low. Also, take a look at your fuses and make sure they are correct. These cars have a tendency to occasionally blow fuses (as listed in other comments on this thread). If the previous owner just put a bigger fuse in to keep them from blowing, that could cause repeated water pump burnouts if the amperage is too high. Finally, make sure you only use quality parts such as VDO, Pierberg, or Genuine BMW

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