Where is the auxiliary pump located on an '03 X5 with 3.0 engine?
 

Hi folks,

Can anyone confirm where this little sucker is located on my 03 X5 with the 3.0 six cylinder?

Realoem makes it look like it's at the lower front of the engine; #17 in this image: https://www.realoem.com/bmw/enUS/sho...diagId=64_1116

A Pelican Parts video makes it look like is under the motor, on the passenger side: https://www.youtube.com/watch?v=o-BpUzAemyQ

Someone on either this forum or other said theirs was right next to/below their expansion tank --- and unless my eyes are failing me, I don't see one hangin' around there.

Any help is HUGELY appreciated. Having issues bleeding the system and the other day heard a nasty noise (with the engine off, heat on high, fan on low): https://www.youtube.com/watch?v=arlkpPqR8KQ . Oddly, it isn't making that noise today, but, ...I am guessing the impeller blades or the bearing/shaft they spin on is failing so complete auxiliary pump failure is looming. NOTE: When that loud noise was happening, there was no flow of coolant (with the expansion tank cap off, bleed loose, and no flow of coolant going down into tank).

Thanks folks.

See additional instructions for the M54 engine: https://www.newtis.info/tisv2/a/en/e...ntrols/OUJOp0y





Here's another link to the e53 X5 aux water pump...see/click link pertaining to M37...there are two links for different engine set-ups: https://www.newtis.info/tisv2/a/en/e...ter-pump/q-M37

Yep, that diagram is just about spot on. Once you remove the air box you’ll see it no problem. It’s a very quick swap out.

Sorry, the real oem diagram. Additionally if yours has failed there should be a code stored in the climate control computer or ecu, I can’t recall right now.

Yellow arrow is the bracket it’s mounted to. Red arrow points to its wires. This is looking down from the drivers side of the engine compartment.

Thank you guys. I'll take the airbox back out (didn't see it), but, curious, as Qsilver's post says I have to detach expansion tank, power steering reservoir, oil filter housing. Does that sound right?

Is that stuff you're seeing in Qsilver's post the stuff for the M62 engine? You've got the M54, so should ignore that stuff.

Also, on this project, my understanding is that this pump is working intermittently for you and your only real problem is an inability to successfully bleed the system, right? I recall a few threads, I think of yours, and may not be keeping them all straight here.

These aux pumps don't seem to fail much. Their use is to circulate warm coolant when the engine is off so you can still get heat inside the car. They of course are also helpful for bleeding the coolant. The main "problem" when they fail is that they make noise. If it were to seize permanently, you would probably never know or care unless you try to bleed the coolant.

So yes, maybe you have that, but you might have other problems in there too, and replacing this may not be the best first step. :dunno:

I replaced the pump on our 3.0i last winter. Just remove the airbox, the pump is situated down there... It's a little bit of a fiddling to take off and on the electric connector. Besides that, it's a quite easy job.

Throwing or not a error code if the pump is not working? In my case no error code...i just noticed that with the car shut off, it wouldn't blow warm air for more then 1-2 minutes, even if the engine was still hot. I guess a error code could come up depending the type of failure in the pump.

Before replacing the pump I finally checked if it worked, by activating the "rest" function with the car shut off. If the pump works, you will feel it by simply touching the expansion tank, feeling a slight vibration by the water circulating. You can also take off the cap of the tank and you will see water flowing trough the small opening.

Once I've taken out the pump, connected it to 12V and it...worked again. Maybe the shaking from taking out the pump did it's job or it was just a bad electric connection. I didn't investigate further at that point and just replaced it...didn't want to do the job again and the new pump was already there.

For your purpose: Try to activate heat at maximum with the car shut off and the engine hot. If you can't feel any circulation by touching the expansion tank (or simply take off the cap slowly and check visually), then your aux pump is not working.

In any case, I don't think that's your problem with bleeding the system.... the main pump generates enough flow to do the job.

Once the air box & tube are out of your way, it’s 2 quick disconnect coolant lines. 1 electrical connector & 2 bolts that mount it to the bracket. That’s all you’ll need to remove. Have some coolant available as you’ll lose some.

No, that doesn't apply to your application. See a "highlighted" image from the "top of the page" from the TIS website (there may have been additional instructions and details further down that apply)...but the expansion tank removal specifically says that it is for the M62 only...you should follow the links and info for the M54 engine:

Thank you SO MUCH everyone.

Very strange, (to me at least), what's going on. The primary issue, I believe, is that after following the same "Bleeding procedure" that is well documented here, I go for a couple hours of driving and the "Check Coolant Level" comes on when I'm done.

I pop the hood and sometimes can see there has been a tiny amount of coolant spray (tiny) that is blowing back on the air flow tube to the air filter. Likely just came out of the cap or something, and as it ran down the expansion tank, the wind from driving blew it back on the air flow tube.

Usually, when I let it sit over night, and expect to just pop off the cap on the expansion tank and top it off before I drive, as I start turning/loosening the cap, I hear ...a volcano getting ready to erupt. Gurgling, bubbling, and sure enough, as I loosen more, it begins to puke out the top. Maybe a cup or two. Then I start the whole bloody process (bleeding) over again.

My independent mechanic, who I trust, has told me, after the 'standard bleeding process', to then drive it, maybe a mile, and see if it's blowing hot air at idle. He also has recommended, when getting back home, to rev the engine to 2500-3000 with the cap off and monitor flow. (I must admit, I've never understood the timing of when to do this engine revving, maybe I was supposed to do it at the beginning).

Bottom line: I cannot properly bleed my coolant system, (I believe), or there is something else wrong that causes the Check Coolant to come on an hour or two of driving after I've bled it.

Some have suggested blown head gasket, but, if that were true, then the pressure would likely dissipate after driving and then sitting all night. Yet, 9 times out of 10, when I let it sit all night, the system is pressurized and coolant burps and gurgles out when I take the expansion tank off.

Last piece of information I can provide is: I bought this vehicle used about 3 months ago with 130k on it. At the time, the owner told me about it needing an expansion tank, but, that it was only a minor thing and he would top it off when going for a drive. First thing I did was buy a new "BEHR" tank, and install it. Same condition of needing to top off continued. I actually thought I could see coolant leaking out toward the top of the tank, at the seam, where the ..."bottom" of the tank comes up to the seam that goes around the tank, horizontally, toward the upper 1/4 of the tank... So I went to the junk yard and grabbed another BEHR tank thinking that maybe I got a bad one. I haven't noticed any leaking, but, I certainly have the other issues I've mentioned. And yesterday, after only a short drive, even though the Check Coolant Level didn't come on, I popped the hood and I could hear the cap hissing; very quietly. No coolant coming out, but, just hissing....

And it was certainly strange that when I was trying, with a cold engine, to do the Bleeding Procedure for like the 8th time, that on that particular occasion, with the engine off, ignition on RUN, heat on HIGH, fan on LOW, that I heard a pretty loud sound, (like a pump gone bad), and there was no flow back into the expansion tank. Every time prior, I would immediate get the flow back into the tank and there was never this loud a "pump" sound. I figured at that point, I need a new auxiliary pump. But after following the Pelican Parts advice, and testing the water valve next to the throttle body and make sure it was getting power, etc., (which it was), and putting things back together, I tried the Bleeding Procedure again, and this time, NO NOISE ...other than a little pump/circulation sound, and a good flow back into the expansion tank. I am very confused.

I know these systems get pressurized, but, ...is something going on that is causing mine to over pressurize? Might I have some head-gasket issue? I've never seen any coolant on the oil dipstick nor do I have that brown fluffy sludge at the top of the expansion tank.

I am planning to bring it to my mechanic and let him wrestle with it. It's gonna suck, because I know it's going to take him a few hours to investigate, test, bleed, drive, check, etc. and that feels like about $300-400. But, at this point, it's probably the right thing to do. I'm pretty confident that, as a 53 year old driveway mechanic, who's done a frame off restoration, swapping of 8-cylinder heads, intakes, carbs, and almost 20 years of BMW E36, E38 and now the X5, THAT I SHOULD BE ABLE TO ADD COOLANT AND DRIVE THE VEHICLE, BUT, CLEARLY I CAN'T.

Thanks everyone. I really appreciate it.

Sorry Qsilver7. As my wife (rightly so) points out frequently that I don't take the time to completely read instructions/recipes ...I went RIGHT BY the part where is says "M64" only! Duh.:dunno:

Lisle 75500 detector from Amazon.
$33.60
For me at least, it is free same day delivery (yes, today).
https://www.amazon.com/Lisle-75500-C.../dp/B0007ZDRUI

If nothing else, it will save your indy from having to wonder about that.

The other easy thing you could try is to replace the expansion tank cap, although I doubt that is your problem.

I had a warped head (practically the same as a head gasket) problem (I mentioned all that in your bleeding problems thread).

Will continue in separate posts to help manage attention span issues.

So with my warped head problem, the car drove perfectly. I had just replaced the radiator and radiator hoses. The cap was about a year old. The expansion tank had been replaced by the PO about 28k miles earlier.

But I was finding little leaks, just like you are. I eventually traced it to the expansion tank cap releasing pressure. I then jumped right on the combustion gas leak detector and was done debugging.

Yes, it was tough to see how the engine could run perfectly and have such a central flaw, but it did.

To try to see how a head gasket / warped head / cracked head could cause your symptoms, consider if this is what's happening:

:D - your auxiliary pump may or may not be failed, and it does not matter at all to this problem.

:D - your bleeding is working fine. As seen on that other thread, there is more than one way to skin this cat, and different methods seem to work well enough.

:D - your coolant level sensor is working fine. Difficult to confirm, since you can't remove the expansion tank cap when the system is hot, and when you remove it when cold, coolant circulates and overflows. You might try to test it with the engine cold, by removing the expansion tank cap and pushing the floating rod down with your finger or pliers or whatever to see if you can make the warning trigger. That should give confidence in a working sensor, but would not confirm lack of a problem there.

:D - your cap is working fine, holding tight up to 2-bar (about 30 psi), then releasing (which it should not need to do unless there is a problem)

:( - when you bought the car, whether the seller knew it or not, he sold it to you with a (possibly very small, maybe worsening) head gasket (or similar) problem, that still persists

:( - your head gasket problem is letting a small amount of combustion gases into the cooling system as you drive.

:yikes: - the gases accumulate, building pressure in your sealed cooling system. When pressure builds to 2-bar while the engine is running, the expansion tank cap releases, letting coolant and gas out, through the underside of the cap, onto the top of the expansion tank. The fan, wind, and gravity take it from there. It lets out whatever it needs to keep the pressure at or below the 2-bar setpoint of the spring inside the cap. This of course will reduce your coolant level, and if enough comes out, you'll get a low coolant level warning.

:confused:- overnight, any of the pressure buildup in your cooling system from boiled coolant will dissipate since the temperature drops and the vapor condenses. But the increased pressure due to the pressurized combustion gases will remain - that gas will shrink according to the ideal gas law, but it will not condense (eliminating any pressure) like water vapor would. Not holding at the full 2-bar (since condensing vapor will reduce pressure some), but at something above zero, depending on how much of the original pressure increase was due to combustion gases, and how much to the vapor pressure of hot coolant.

:( - when you check in the AM, with a cold system, the hoses will still feel pressurized, and when you release the cap, coolant will gurgle out due to the pressure.

That's just a theory. May or may not be true. For your sake, I really hope it is not the case here. But it would fit the facts. Would be easily testable with that Amazon Lisle 75500.

Thank you SO MUCH for all your help here, Oldskewel. I am scared to think that you're right, because nothing seems to make sense here ...other than the combustion gases getting into the coolant system. I will get that tester and test.

I would assume that, if the head were warped, it's probably a $2500 job for someone to fix? I almost paid that much for the vehicle. May just have to get rid of it --- or drive it and keep putting coolant in all the time until it fails?

Damn. Will update when I get the tester. Thank you,

Jay

Good move on the tester. Thinking even more about it, I think the theory laid out above explains the pressure you're seeing, and I can't think of any other possible explanation. But the tester will give the answer. To use it, you'll need to find a vacuum hose somewhere to disconnect and give yourself access to manifold vacuum. That basically provides a slight suction to draw whatever vapor is circulating through the coolant, through the test fluid in the tester. After a few minutes, if you have combustion gases, the fluid changes color. Very definitive. Toughest part for me was in finding an easy vacuum port (not too hard, but I don't remember what I used).

On the pricing of the rebuild, yes, it might not be worth doing. I did it all myself, using good parts, trying to get good deals, spending a lot of time learning and following the 50skid youtube series. It was educational and enjoyable, and wow the thing is perfect now (until the AT breaks some time in the next 100k miles). My total out of pocket cost from special tools, parts, and machine shop fees was around $800-$1000. Paying someone, I'm sure they would not have done as good a job as I did (e.g., I put TimeSert inserts in the block for the head bolts), and I can hardly see how they could charge only $2500 for it.

So if doing it yourself and your time is free and you'll enjoy it, it's worth considering. Otherwise, selling to someone like that may be the best bet.

Like I said in one of those other threads on this, having been through my problem, I will never look the same way again at a craigslist ad for a BMW (especially, but other cars too) that report problems with unknown coolant leaks or "needs a new radiator", etc. Having that Lisle tester along for the inspection on any future cars will be nice.

And on my 2001, just guessing what happened, records show some significant problem at 158k miles in 2013 (CCV explosion, expansion tank replaced, etc., valve cover, MAF, DISA, transfer case [unrelated]). I bought it 9k miles and 1 year later in 2014. It worked fine for several years until in June while my son was driving it late at night. Not sure if a slightly warped head finally warped enought to blast through a weakened ORIGINAL upper radiator hose (seriously, the dealer did $14k in repairs on that over the preceding 18 months, and left in the original upper radiator hose???), or if the failed hose caused some overheating which caused the warpage to get worse. Either way, it's a known Achilles heel to these otherwise great M54 engines.

Also - if you do get to a position of deciding to unload it for next to nothing to someone who would rebuild it, I expect there may be band-aid fixes you might try. I did not look into any of those, but head-gasket-in-a-can ??? , I don't know if some repair involving oversized head bolts that could be done without removing the head (just take off the valve cover, and the head bolts are accessible), or something else. I was wondering about these things while I was wading through the project, which did turn out to be way huger than I had expected.

I look at repairs compared to a new car payment of $400 per month. If you go 6-1/2 months after the repair, you're money ahead. Plus you have the confidence that the cooling system has been properly serviced and the head assembly refreshed as well. My repair bills so far in 2018 have been about $1800.


2002 X5 3.0 348,600 miles
2014 428i 41,000 miles


2004 325i sold at 123,600 miles
2001 325i sold at 66,000 miles


1970 Firebird under restoration

What is the sale price of a car with a $400/month payment? About $15k?

If this one does have a head problem, what's its value as it sits? $1k? jpilk99 will know what the rest of the car is like - suspension needs, AT, paint, wheels/tires, battery, etc.

Considering this car was bought for less than $2500 a few months ago, what would be the value of this car after the (estimated) $2500 repair? $4000?

What would a similar, but problem-free x5 cost? $3500? If so, that is the comparison to be making, not vs. a car payment on a $15k car.

Other factors are the concept of the devil-you-know issues/not with the car you've got vs. trading for a new set of unkowns. But jpilk99 bought it fairly recently, and may not yet know all the problems, etc.

I've given guesses of answers to these questions. These are the questions that should be considered in making a rational financial decision here. Comparison to buying a $15k replacement is not an apples-to-apples comparison. That's like deciding to buy a new Cayenne Turbo S because it costs less than a Bugatti.

Having been through this all on my x5, I thought long and hard (including throughout the process) about how much sense it made to repair a car where the value of the repair was comparable to the value of the car itself after being repaired.

It really does feel good to know how well it runs now, since I did it myself. Not sure if I'd feel so good if I had paid someone else to do it. In the latter case, I'd think of it more rationally financially, and would probably not be so happy. Another factor in my decision was in knowing all the repairs (suspension, doors, etc.) I had been through and knowing how good shape it was in other than this single new problem. Surely if selling it, I would not have recouped that value I put into it.

The other consideration if doing the repair is the risk. Really, I was thinking of this quite a bit during the repair. Like, what if I get all done after all the $$ and effort and time ... and it has the same problem or a different problem and I then realize I made a mistake along the way. That would suck from about 5 different ways. Decisions all the way through the process on what risk vs. cost decisions to make - TimeSert, remove block, grind valves, valve guides, valve stem seals, replace fuel injectors, replace oil pan gasket, oil pump, chain guides, BMW vs. OEM parts, etc.

I bought my X5 in 2006 with 53,000 miles on it for $23,800. Payment was $385 for 66 months. The CEO's 2014 428i was purchased with 12,000 miles on it at 16 months of age for $36,000. Put $10,000 down and have a payment of $405 for 66 months. I keep my credit score high.

With the no rust situation we have in Texas, vehicles last a long time here with proper lubricants and maintenance. When the valve cover was replaced on the X5 at 325,000 miles, the technician could detect no wear on the timing chain or cam lobes.

2002 X5 348,600 miles
2014 428i 41,400 miles

2004 325i sold at 123,600 miles (This was traded in on the 428 and the dealer sold it for $7995 because it was in such good condition)
2001 325i sold at 66,000 miles

1970 Firebird Under restoration

jpilk99, this thread might have similar problems / help, related to your situation. Since it came out about the same time yours did, I may have mixed up his problem with yours. But I usually try to make my answers generally correct, so that probably still applies.

https://xoutpost.com/bmw-sav-forums/...ising-bit.html

Hope you get good test results.

I was servicing my cooling system and took out the aux water pump. I connected it to 12v and nothing happened.
I guess it's dead...
I just ordered Hella auxiliary pump for $140 CAD from Rockauto
Another option would be Airtex for $350, but I think that's a bit too much.
I took apart the dead pump and it looks like it's easily rebuildable if you know what to do :)