[queensfield]

Thank you- I must have been blind when I looked. Pardon my ignorance, but why do the codes need to be cleared first before installing new pump, thermostat and vanos solenoids?

[Saintor]

Originally Posted by pruettfan

Pretty much all the E90's use the same water pump so it is just a matter of time. I looked up the part number and it is used on a ton of BMW's.

what can I say? It is just an "epidemic" observation against all odds. Still waiting for the 328i.

[ENINTY]

Originally Posted by queensfield

Thank you- I must have been blind when I looked. Pardon my ignorance, but why do the codes need to be cleared first before installing new pump, thermostat and vanos solenoids?

The procedures I've done from the Bentley say to clear the codes first.

[omerfar23]

Originally Posted by ENINTY

I guess so, but I'm disappointed a bit about the engineering. I get it, the water pump has a tough job. It has to push very hot water around for long periods of time. BMW's idea about using an electric water pump is a good concept, but poor in execution on their part. First off there are no warning signs (other than the fault codes - but how many owners except a gearhead like me would ever know they are there), second there is no water temp gauge to keep an eye on engine temperature (yes the 335i has an oil temp gauge, but that'll not do you any good to indicate a pump failure), and finally the over temp warning is almost after-the-fact; my car literally when from normal condition to overheating (red indicator symbol) in about 5 seconds. If I was stuck in traffic, say in the center lane of a 4 lane freeway, I can't imagine how much engine damage would have occurred. I was lucky because when my car indicated an over temp condition I was able to pull to the shoulder and shut the engine off in maybe 10 - 15 seconds. But I knew exactly what had happened because a) I knew my water pump was suspect (throwing codes), b) it was high-mileage, and c) I knew the conditions of over temp from reading the owner's manual and from threads on this Forum. The typical BMW owner knows none of these things and would let the engine seriously over heat, which could really damage the engine with a blown headgasket, or worse a warped cylinderhead (fingers crossed my car has no such problems).

It's a poor design. Most (belt-driven) water pumps have a weephole that begins too leak and provides a distinct smell of coolant to give you some time to have the car inspected and repaired before the pump fails. Other belt-driven pumps are driven from the camshaft belt and have a periodic replacement schedule that coincides with the cambelt replacement interval, so they rarely fail. And most belt-driven water pumps DON"T COST FUCKING $500. It's fine to design an electrically driven water pump, and it did go 150,000 miles (which is attributable to the fact it's not driven off a belt), but the pump also costs over 5-times as much as a conventional belt-driven pump, so where are the life-cycle maintenance savings I expected to get from this design. And there are no fuel cost savings (to the owner) because what ever fuel mileage is gained by driving the pump electrically is lost in the repair event. Even though the pump is a fancy electric motor driven design, it doesn't need to, and it shouldn't cost $500 (and the new unit is a remanufactured part to boot!).

The obnoxiously priced pump is what kept me from replacing it before it failed. Having a road-side breakdown cost me a towing bill of $200 (my insurance covers $100 of the total $300 bill). If the pump was reasonably priced, say $150, I would have replaced it when I did the thermostat back in February with 134K on the clock.

So if this happens to an uninformed owner, say a 34-year old young female executive who is concentraiting on her career and pays no attention to her car, she'd be out $200 for a towing charge, $500 for the part, and $500 for the repair labor. Think she'll ever by a BMW again when a water pump replacement costs $1,200 (even if it is covered under a warranty). I doubt it. BMW needs to rethink this design.

Considering how BMW is starting to go engineering-wise and build quality-wise, this will probably be my last BMW (and I've owned a 3-series since 1989). They are just getting too stupid with the over engineering.

Just my rant.

I completely agree with you and feel your pain. my 335i's WP just went out at 39K. so pissed. I am going to do it myself and I understand WP burn out but 500 for WP is ridiculous. E36 WP is only 200 for god sakes..

The forum needs to very detail and awesome DIY For this ...

[RentonTDI]

ENINTY et al, -

Thanks for all the good info in this thread; I've started tracking info on my water pump, as shown in thread below.

I've got a 2009 e90 (~70k+ miles) and expect to use this info to replace the pump when it starts to generate faults, and not prematurely. Wish me luck

http://www.e90post.com/forums/showth...4#post12800114

[evssss1]

Guys, I believe my car (05 E90 325i) might be running into the same issue.

I spot the 2E81 code.... cleared it and it showed up again after a trip.

Seems my pump is going. Weird enough though, the RPM did drop to 0 according to the record but I did not get any overheating warning (YELLOW or RED).

So I'm not sure if it is a sensor issue or the pump issue itself.

Having said that, according to OBD2 reading the coolant temperature is maintaining around 100-105 degC (not F) under daily drive. Is it normal?

[Efthreeoh]

Originally Posted by evssss1

Guys, I believe my car (05 E90 325i) might be running into the same issue.

I spot the 2E81 code.... cleared it and it showed up again after a trip.

Seems my pump is going. Weird enough though, the RPM did drop to 0 according to the record but I did not get any overheating warning (YELLOW or RED).

So I'm not sure if it is a sensor issue or the pump issue itself.

Having said that, according to OBD2 reading the coolant temperature is maintaining around 100-105 degC (not F) under daily drive. Is it normal?

The 2E81 code should indicate a slow pump speed deviation from the max pump speed of 250 RPM. It will not show a pump speed of zero. The car will not overheat in this condition. 2E82 is the code for a completley failed pump i.e. Zero RPM; where the car WILL overheat. Get the pump changed very soon, before it completely fails.

[evssss1]

Originally Posted by Efthreeoh

The 2E81 code should indicate a slow pump speed deviation from the max pump speed of 250 RPM. It will not show a pump speed of zero. The car will not overheat in this condition. 2E82 is the code for a completley failed pump i.e. Zero RPM; where the car WILL overheat. Get the pump changed very soon, before it completely fails.

In the freeze frame it showed the last occurance of 2e81 which the RPM is 0 and deviation is 250.... it is weird that it has no 2e82 logged.

Anyway I am getting a new one and get it replaced soon....probably with the tstat.

[Efthreeoh]

Originally Posted by evssss1

In the freeze frame it showed the last occurance of 2e81 which the RPM is 0 and deviation is 250.... it is weird that it has no 2e82 logged.

Anyway I am getting a new one and get it replaced soon....probably with the tstat.

I guess it could do that for an instant. 2E82 is when the pump shuts completely off. Don't wait too long, like I did and get a tow bill to boot. If you can DIY, it's not too bad of a job.

[Brad from the OC]

I just replaced my water pump and t stat today as a preventative measure. 50K miles, but didn't want to risk an unplanned breakdown plus a $200 tow bill. Took it to an Indy gave him the pump, t stat, bolts, and coolant and he charged $270 for labor. So for just $70 over a tow bill, I have a new pump and new coolant and should be good for another few years. Cheap insurance in my opinion.

[NoTempoLimitN54]

Originally Posted by ENINTY

And BTW, the warning totally sucks: Ding! Yellow coolant over temp warning, 2 seconds later RED coolant over temp warning... Dove for the sholder (light traffic thank God) and shut it down. Coolant puked from the reserviour.

I'd been told that when the water pump fails, you go into limp mode for the overheat, and then the engine shuts down to protect itself when the pump fails. Did that not happen in your case?

I too would like to have a coolant temp gage, but I'm glad to have the oil temp gage rather than that totally useless MPG gage (E92 335i). Perhaps someone could come up with a way of coding the DME to make the MPG gage behave as a coolant temp gage for the non-turbo guys.

I believe some of the N54 software tuners have found ways to make the gages display different info that what they were intended to display.

[woodpecka]

Anobody knows if we can get the fault codes with INPA and how?

[index1489]

The miles before the pump fails is irrelevant, it fails after hours of operation not miles.


1 car could have 150k miles and driven X hours (lets say lots of freeway driving)

2 car could have 75k miles and driven X hours (lots of city traffic stuck at lights)

They could both have the same amount of operating hours and the pump fails around the same time.

Of course when people say the pump failed at 30k or whatever thats just a defective pump.

[Efthreeoh]

Originally Posted by index1489

The miles before the pump fails is irrelevant, it fails after hours of operation not miles.


1 car could have 150k miles and driven X hours (lets say lots of freeway driving)

2 car could have 75k miles and driven X hours (lots of city traffic stuck at lights)

They could both have the same amount of operating hours and the pump fails around the same time.

Of course when people say the pump failed at 30k or whatever thats just a defective pump.

Not sure I agree with this totally. The pump fails because the electronic control components are mounted on the rear of the pump housing and are heat cycled to death. I think the failure is more of a function of heat soak rather than just pure running time of the pump. Meaning, a two cars could have the same operating time at different mileages, but if one car is in Dallas, Texas, and the other in Juneau, Alaska, I'd bet the Alaskan car's pump would last longer.

[SpartanGA]

Interesting thread. I had heard about these expensive electrical water pumps from my Indy. My 550i doesnt have one ,but my 2011 e93 does.

Regarding the plastic impeller, these are very high quality pieces. Being in the plastic industry, this is very common and the engineers love the advantages of weight and ideal vane design for pump efficiency. Stainless stamped/welded impellers offer poor efficiency and cast are heavy and typically have a much rougher surface finish.

Hell, airplane bodies are 'composite'.

[Saintor]

Originally Posted by Efthreeoh

Not sure I agree with this totally. The pump fails because the electronic control components are mounted on the rear of the pump housing and are heat cycled to death. I think the failure is more of a function of heat soak rather than just pure running time of the pump. Meaning, a two cars could have the same operating time at different mileages, but if one car is in Dallas, Texas, and the other in Juneau, Alaska, I'd bet the Alaskan car's pump would last longer.

That's my impressions too. It looks to me that there are more cases in the southern part of N. America than in New England and above. Possibly that the batteries last longer here too.

[index1489]

Quick question what modules are those codes thrown? The DME correct? So far nothing on my car 120k.

[freshnezzz]

water pump died 2 weeks ago. broke down, towed, $900 later, replaced and running good again. suck it costs so much

[Efthreeoh]

Originally Posted by index1489

Quick question what modules are those codes thrown? The DME correct? So far nothing on my car 120k.

Correct DME. Code can only be read by a BMW scan tool; they do not show up as OBD II codes.

[woodpecka]

Originally Posted by Efthreeoh

Correct DME. Code can only be read by a BMW scan tool; they do not show up as OBD II codes.

What about INPA?

[Efthreeoh]

Originally Posted by woodpecka

What about INPA?

If it can read BMW's codes, then yes.

[bkmaster02]

does anyone know what the consequences of installing a new water pump/thermostat without clearing the codes first would be?

I'd like to do a DIY replacement, but don't have access to a BMW scan tool.