Alternator problem
 

Hi have 05 x5 4.4. When i first start driving in the morning in about 10 minutes
I get 4x4 light and flat tire lite. I had codes read and they point to voltage being low.
So i started to monitor voltage by a voltmeter.
When i start the engine in the morning a voltmeter shows 12.55. After about 10 minutes i hear some noise from the alternator and voltage jumps to 14.5. At this point engine rpms drop momentarily. Feels like the alternator was not engaged and suddenly it got engaged. If is start driving now i never get 4x4 light. Any idea why is it engaging so late? Could it be that the belt is loose or is there
A built in mechanizm in the alternator to activate/deactivate it? Or is it just alternator gone bad?

Once it "activates" and voltage reaches 14.5 it is good for rest of the day. I can shut down the engine and then start it and voltage is good. It only happens after the car has sat overnight.

Really looking forward to hearing from you
Thanks

I think your voltage is too high for an X5. The usual voltage is in the 13.85V range for the highest point with these alternators. I would suspect the regulator pack but would change the whole alternator if I were doing it. In your case with the 4.4 engine that is not a cheap repair.
GL

I just want to be sure its the alternator. Anybody else with same
Symptoms? Whu would it be expensive? I s aw some rebuilt alts.
For less then 200 and my mechanic says he can swap it in an hour.

Does he know it is water cooled?
$200 seems a little low but maybe you're getting a deal somewhere. I would be looking at a specialist supplier such as Bavauto or the like to be sure I was getting the proper part and it was not some thrown together reman such as those your get from Autozone etc. I have heard nothing but tales of woe from people who have fitted these parts and had to go through the fit - remove- replace - fit remove-... dance several times before they gave up and bought from specialist. While the companies involved did honor their warranty each time there was still the labor cost or waste of time involved performing "field quality control" testing.

I looked and i did not see any water hose going in the alternator.
Are you sure 05 4.4 has watercooled alt. ?

You're correct! It seems to be a standard alternator so it is no big deal. (I checked on realoem.com) Puts a whole different light on things.

I guess this is what threw me??

http://www.xoutpost.com/bmw-sav-foru...lternator.html

What do you think about Bosch rebuilt ones from reputable part dealers?

Depends on who did the rebuilding and where. Every reman I have read about that had problems seemed to have been rebuilt in Mexico. There may actually be some quality rebuilds from there but.....
Ask who did the rebuilding and then check them out as much as possible online. It is so hard to make a buck in today's market that retailers are being forced into using suspect suppliers just to compete.
I have read about big name electronic component supply houses getting caught out with batches of look-alike Chinese made junk. (Pun intended.) It cost them mega $$$$ to put right and their good name was ruined.

i would say to get a lifetime warranty one if it breaks again at least you can get another one free, (only pay for the labor), mine was with water cooler for my 01, paid 345$ at riebes auto parts with lifetime warranty.

goodluck,

my mechanic is getting eom one from dealer fro 600 something dollars
he is saying he has to remove radiators upper hose to get to it.
which means new coolant and coolant bleeding. Wonder if its possible to
get to the alternator without messing with coolant hoses.

here is a DIY for you friend...

and yes,you need to add coolant, some hoses needs to come out.

here why ,top hose attached to the alternator...

http://i1140.photobucket.com/albums/...pwaterhose.jpg

600$ is a lot of money...ohhh

Thanks for the diy link. it looks like lot of work. I just put new waterpump in it two weeks ago and I wish I had know the alt. was bad too. Now all the hoses have to come off again. I have a voltmeter now hooked up to a cigarette lighter and everytime I start it I wait for voltage to climb to 14 volts and its fine. maybe i will drive like this for a while before it completelly goes out :-).

well,there is a place here in my area ,from what i know ,one of my family member ,had some problem like you have ,voltage,and he replaced it with a used one for 150$ with 6 or 12 month warranty (not sure 6-or-12)...

my alternator ,everything was fine and then one day i start hearing some big noise coming from the front, in my case a bearing was the problem,but i put new one for about 350$ with lifetime warranty at riebiest auto parts.

goodluck,friend

Alternator Removal
 

Yesterday I removed the alternator. I thought I would have to
disconnect coolant upper hose from the radiator but after I took out electrical fan there was enough space to work in there. So after removing the belt there was not much to it. Just tipped it upwards and pulled it straight forward. it is very heavy and you have to support it somehow before you get wires disconnected from, it almost broke my back.
I am getting a new one from the dealer so I will just put it in and see if voltage is constant 14+ volts. So now I know for sure 2005 4.4 x5's alternator is not watercooled and there is no need to remove radiator hoses and refill the cooling system. So all those Alternator DIYs floating out there are for older pre-2004 x5s and on those it's a real pita job. I just had to be extra carefull not to tear any radiator hoses.

Bosch usually run 13.85V for the upper limit. Pretty steady at than under all loads. (I ran a digital VM during driving for a couple of weeks just to confirm after I got the vehicle.)

I'm having the same problem with my X5 4.4 sports 2005 but other than occuring randomly, also happens at the worst possible time- on the freeway. Trans goes to limp mode, get all kinds of crazy lights in the dash (multiple faults) such as DSC, 4x4, airbag etc. I have DIS and all the time error points to communication problem DME/alternator, DME shutting down the alternator and thus low voltage to components (explains the multiple faults). All I've had to do is turn the car off and wait for 10 or so minutes and startup again and car runs fine! I removed the alternator (yep, it's NOT water cooled), checked and cleaned all connections, cleaned volage regulator and alternator, installed new battery but all to no avail.

I'm surprised you had a relatively easy time removing and putting back the alternator. I had a nasty time and had to put grease on the edges to push it in while installing it. Removing it was a nightmare. TIS and Bentley manual are all wrong saying to remove alternator straight forward. No, have to first tip it towards driver side then straight forward and out.

I'm also planning to replace the alternator. Cravier BMW dealer quotes $500 with 2 years warranty. I'm also wondering if it's just the voltage regulator ($140) that needs to be replaced.

Please let us know if your issue is resolved after alternator replacement.

Thanks!