[blown07]

I've read the n55 guys having this problem but has anyone had this issue with the water pump running way too long after the car is shutoff?
Sometimes when I shut the car off, get out, close the door, wait for the start/stop button to turn off.....5 seconds later the water pump starts running....the engine is not that hot when it happens...I did notice when it happens the gear level indicator stays lit on park when the start/stop button turns off....still running and it's been 1/2 hour...Help.

[3000GT MR]

Originally Posted by blown07

I've read the n55 guys having this problem but has anyone had this issue with the water pump running way too long after the car is shutoff?
Sometimes when I shut the car off, get out, close the door, wait for the start/stop button to turn off.....5 seconds later the water pump starts running....the engine is not that hot when it happens...I did notice when it happens the gear level indicator stays lit on park when the start/stop button turns off....still running and it's been 1/2 hour...Help.

most of the time I've heard or seen this issue it had to do with pcv heater element. Looking at the wiring schematic a while back I remember a few other things that could cause this. A few off the top of my head were, a open circuit in any of the following: a secondary O2 sensor, ocv heater, water temp sensor, and a few other sensors I can't remember exactly which ones

[rxrome4]

I Just had this problem water pump went on my 2007 335 CIV had the pump and thermostat replaced today. my mechanic called me to pick my car showed up 3 hours later and found my car smoking the water pump melted also the connector. any help would be greatly appreciated I'm thankful my car did not catch fire but now i ordered a new pump and piggy connector to it and hoping the pump was defective

[blown07]

Sounds a little different than my problem. My pump will occasionally run for 1/2 hour when it's shut off but it seems to be related to when the residual heat button was used. I know the pump is supposed to run during residual heat but even after I shut it off it seems to effect the pump for a few more start/stop cycles.

[scottp999]

Define way too long? If it really is 30 min, then that is crazy, you probably have a sensor or cpu problem that makes the engine management software believe the water pump needs to continue running. The water pump running after shutoff is a normal event with N54.

"It is possible in conjunction with the N54 engine's electric coolant pump even after the engine has been switched off to dissipate the residual heat from the turbochargers and thus prevent the lube oil in the bearing housing from overheating."

"Electric Coolant Pump
The coolant pump of the N54 engine is an electrically driven centrifugal pump with a power output of 400W and a maximum flow rate of 9000 l/h."

"The coolant pump also operates differently than conventional pumps when controlling the engine temperature. To date, only the currently applied temperature could be controlled by the thermostat. The software in the engine control unit now features a calculation model that can take into account the development of the cylinder head temperature based on load. In addition to the characteristic map control of the thermostat, the heat management system makes it possible to use various maps for the purpose of controlling the coolant
pump. For instance, the engine control unit can adapt the engine temperature to the current operating situation."

"Intelligent Heat Management Options
The previous section dealt with the various temperature ranges in which heat
management is effected. However, an electrically driven coolant pump makes available even further options. For instance, it is now possible to warm up the engine without recirculating the coolant or to allow the pump to continue to operate after turning off the engine to facilitate heat dissipation."

Component Protection
• After-running of electric coolant pump = improved heat dissipation from engine switch off point. Allows protection of turbochargers by reduced oil “coking” during heat soak.

From: http://www.e90post.com/forums/attach...8&d=1165592709

[rxrome4]

My problem is that the pump did not turn off after the car was shut off and caught fire New water pump and thermostat and it was fine before no issues with pump running after car shutoff

[Fredo75]

I just finished replacing mine right now. It seems like I'm encountering similar problem like you rxrome4. While I was replacing the last hose I could feel the heat coming from my 2nd hand 2012 pump. After I filled up the coolant reservoir and carried out the bleeding, The key was out of the car and coolant started spilling from I don't know where until I disconnect the pump. After looking at the connector, I could always sense a constant 12v to the pump. Anybody has encountered that? Could my pump be simply faulty even if it's running?

[speedhunter93]

I'm encountering the same problem the water pump keeps cycling on after I turnoff/lock the car until the battery dies

Did anyone findout the solution?

[Cuticuti]

Please update the result. I am currently having same problem with new water pump & Tstat installed. Thanks

[waool2016]

Originally Posted by speedhunter93

I'm encountering the same problem the water pump keeps cycling on after I turnoff/lock the car until the battery dies

Did anyone findout the solution?

anyone found a solution??

[Cuticuti]

It was a bad water pump

[waool2016]

Originally Posted by Cuticuti

It was a bad water pump

after the new one??