Failing Water Pump?

[drwillb]

On Tuesday, half a mile from work, my yellow coolant temperature warning came on. Being "almost there", I continued slowly to my office building and the red death temperature warning came on.

Sidenote: why on earth is there no possible way of displaying the coolant temp on these cars, even with iDrive. All we have is the high-tech equivalent of an idiot light from the '70s.

Lunchtime rolls around and I went out to check on the car. Overflow tank low, added 8 oz. of distilled water to get the level back to normal.

Evening time comes and I drive home uneventfully. I had some time to think about things and checked on n54tech for JB4 settings. Sure enough, steering wheel menu 7, item 6 hijacks the oil temp gauge to read coolant temp. This is good but the scale on the dash gauge doesn't make interpreting temperature easy. I then turned on the iPhone app for JB4 and, lucky me, the oil temp gauge on the app reads the hijacked dash gauge data, not the actual canbus data for oil temp. Therefore, JB4 iPhone app oil temp gauge was reading coolant temp with an analog value!!

Wednesday morning comes, I drop my son off at school, then have to go down Main St. with lights and traffic. iPhone app shows rising coolant temps and I finally pull over when it hits 215 F. At this point, the main fan is running at monsoon speed, which I've never heard before, other than on the prior morning's overheat condition. Prestige BMW, Ramsey, NJ is one mile away at this point so I called and took the car right in. I got my loaner, went to my scheduled meeting and left the dealer with what I thought was a pretty cut and dry situation. Especially when you consider my car has 60k miles on the original water pump.

Thursday afternoon now. I return the call from my service advisor to hear that the tech plugged in their diagnostic computer and didn't pull any codes or faults. In today's BMW world that seems to mean the techs behind the curtain have no fucking idea what to do because these guys are only trained to read what the computer monitor spits out at them. Today's mechanics have no diagnostic skills. I thought this was only happening in medicine.

The service advisor said they could go ahead and replace the water pump and thermostat, as per my request, if I wanted, but the "almighty" computer didn't think they were a problem. I asked how much: $1800. I had to hold back from actually saying F YOU. Seems the parts are $900 bucks and the labor is a whopping 6 hours. Now, initial reaction would not have been without merit if you consider that I had done some homework on Tuesday evening. $600 will buy you all the parts from either ECS or Turner, and that's for a VDO pump. I also looked at the BavAuto video for the job and my mental calculation came out to somewhere between 2 to 3 hours for the entire job, including getting the car off the ground and taking the bottom shield off. So, $1800.....F YOU.

On top of all this, I asked if anyone had taken the car out on the road. Something with traffic lights and traffic would seems appropriate. The answer was: the tech let the car idle for a long time. Everybody, join in: F YOU!!

I turned in my loaner tonight and brought the car home. Temps were around 206 F all the way home but that's mostly highway. I then sat in the car in my driveway and the temp had climbed to 217 F and the fan was right back at monsoon speed. BTW, ambient temp was below 50 F.

So, my car guy senses still tell me the water pump is well on its way to puking its guts out.

Does anyone have any other opionions on this?

Thanks.

[shawnj]

I had the same symptoms. Def the WP/T. If it won't fuck up your warranty (if you still have one) go to an indie. I recently had my WP/Tstat AND the Radiator replaced with OEM for $1,800 and they provided a 1 year warranty on the parts. If you are good at the googles, you can find even cheaper prices for those parts and if you want to get wild, you can replace that shit yourself

Edit: JB4 doesn't read codes? I used Carly to check mine out. It came up with different things like Shutting Down Cooling System Due to Blocking and I forget the other shit off the top of my head.

[blue135]

drwillb; I regularly run coolant temps at 215-220 F with dead steady at 240. Oil temp is from dash gauge and coolant read with Scan Gauge II/OBD. At those temps, no high fan speeds, no engine lights, etc. Wonder if the water pump is really bad (especially given dealer analysis).

Just as an aside, my Colorado V-8 runs water temp 205-215 in FL heat, and wife's Genesis V-6 runs 185. All this to say that BMWs appear to run at high end of spectrum so 215 may not be out of line.

[drwillb]

Shaw, I did use the JB4 to check codes: none were there. Same as the dealer.

I'm a handy guy so I can do the job myself but now it's Friday and parts from the internet will need to be overnighted.

[Stewy_604]

I did the water pump and t-stat last summer, was a bit of a PITA. The water pump was the first failure. Since they usually fail around the same time or in pairs, I replaced the t-stat while I was at it.

[drwillb]

Just got back from the dealer, water pump, thermostat, bolts , u-shaped hose, and a gallon of their finest coolant. $650 total, not bad for dealer pricing if you add overnight fees to internet sourcing the parts.

[Stewy_604]

^^ Not bad at all considering.

[ianc]

Good call on picking up the parts. I think you will find you are a bit off on your 2-3 hour guesstimate though... ;-)

Took me 6 with lunch and so forth, but no way the dealer should be charging that....

ianc

[twinboost_MD]

when the water pump fails it fails. It goes from 100 to 0 theres no in between so it cant slightly fail or be running poorly.. if its dead it's dead

and your temps are fine now so sounds like the thermo but yea replace the wp if ya want.. general rule of thumb: if it ain't broke don't fix it and they fail very randomly.. so you might replace this one and the new one will fail at 20k when you can prob get 20k more out of this one. I would wait and do the easy fix for now

[drwillb]

I'm at 60k now so, according to many reports, I'm right in the failure window for the pump.

As the ambient temps have been going up so has the speed at which I overheat. By that I mean 240 F with red dash warning.

You may be right about it only being the thermo but the pump can't be far behind.

Anyway, got it done last night. 5 hours total but it would have been 4 hours had it not been for the AA FMIC and ER competition oil cooler. Between the additional bulk of the IC and its larger inlets and the oil cooler lines running right where you're supposed to stick your hand in to get at the 3rd bolt it was a complete roadblock.

I checked the Bavauto video a couple more times, thank God for high def, to get a better understanding of what I needed to do. I was ready to start pulling oil cooler hoses off but then realized I could loosen and lift the radiator fan. This gave me just enough room , barely, to get my hand in but that 3rd bolt was still a tough go.

Another sticky point was pulling the hard hose with the clip connection off. Again, I had limited space and that sucker just didn't want to slide apart.

I got it all done and saved $800 in labor at the dealer. That's a win.

[drwillb]

Drove to work today and coolant temp peaked at 230 but it did come down to 224-226 on it's own.

I did set the JB4 to map 1 and from my recent experience with nursing the car along I can tell you that there's a big difference in heat generation between map 1 and map 4. I'm guessing it's related to pre-boost and increased throttle response. At its worst point, I was running the car on map 4 and the heater on full blast but still managed to overheat (red dash warning) under those conditions.

So, what is considered "normal operating temperature"? By that, I mean at what temperature does the DME start to reduce power?

[ianc]

I feel your pain on that top pump bolt. Even pushing the rad fan up, the top of my left hand was all bruised for days. Bastids in Munich are probably laughing fit to bust a gut, and that Otto fellow from Bavauto must have hands smaller than Donald Trump...

ianc