Any BMW car specialist out there ??

[dpcarson]

OK, I have a 2005 525i that has never given me any trouble and I sing it's praises to everybody that always wants to ask me about maintenance.  However, last night I went out to eat with the family and this thing literally grew a mind of it's own while we were in the restaurant.  I came out and tried to start it and it would fire briefly but not run.  Then the windshield wipers came on and would not go off.  Then the cruise control malfunction light came on and the passenger air bag and passenger restraint malfunction light came on.  After several tries it finally cranked up but all the malfunction lights were still on and the windshield wipers would still not turn off.  I did not have any tools with me but luckily Kickback Jack's is across the street from Lowes so I drove across the street and figured I would try disconnecting the battery for a few minutes and see if everything would reset.  When I hooked the negative cable back up it fired up and seemed to run fine the 20+ miles home.  This morning when I go to head out to work for a while, the car cranks up fine, then about 1/4 mile down the road the passenger airbag and restraint light comes on again and I started hearing what sounded like a whistling noise.  Even on flat road the rpm's are also inconsistent with 300 - 400 variation with the cruise control set at 60, and normally the gauge shows me at about 30mpg at that speed but this time it was only showing me at about 12 mpg.  Then the flat tire warning light comes on and I know the tire is not flat.  

So, other than demonic possession, anybody have any ideas?  Thinking it may be time to sell it and get something else, but dang it has been an awful good car.  139k miles with nothing more than routine maintenance and a valve cover gasket.

[Jess from VA]

Time for a code reader check?   Or an exorcism.

Know nothing about Beemers.  Dang new fangled sensors/computers/inter-connectivity are great, until they're not.  Could it be as simple as a failing battery (volt regulator/alternator) (enough juice to run the car, but not all the computers)?

Me, I go to vehicle-specific forums and search for similar symptoms, and maybe learn something I didn't know.

I lost a cam position sensor on my Dodge, and then it ran like it was demon-possessed (bad, normal, bad, normal...just to keep things interesting).  For all the world, it made me (the car) look just like a really drunk driver (lurching). They really hate drunk drivers where I live, and I was afraid I was going to get an M16 stuck in my ear and a colonoscopy before I made it home.

 I had never before heard of a cam position sensor, and figured I needed a cam that knew where it was without a sensor.

Even before a code reader told me what it was, I had found lots of Dodge guys with the same exact symptoms on a Dodge forum.

My brother is the finest mechanic I've ever known, and his solution is simple.  He refuses to own or drive anything made after 1967-8.  His only computer is changing points to an electronic drop-in part. His trucks are utterly reliable, but entirely lacking in creature comforts; his windows still roll down by hand.  LOL

[..]

Have you tried taking it to a car parts place and letting them plug in their  hand held diagnostice reader?

I've done that at Autozone and PepBoys.

[art]

I'm with your brother. My newest car was an 01 Kia,POS.  We were just riding around town when bang. I heard a loud popping from under the hood. It blew a spark plug out of the alum. head and took out the coil. Got it fixed for $800 and then a week later the oil pump went out. I fixed it myself and then sold it. My favorite ride is my 93 f 150 and my wife's 95 Buick. As to the Buick it too has too much electronics on it. Cost me $400 to replace the ignition switch.

[BF]

BMW = Bring My Wallet

[sandy]

Trade it in on a car of quality instead of status. The new Beemers are among the most complained cars today. My neighbor has a Toyota Avalon loaded. She's around 100K with no major issues. I've driven it and it's a hot rod with the V6.

[Robert]

You more than likely have a can bus problem. Meaning think of cars as a building with many computers that all talk to each other. When one ties up the line they cant speak to each other and they begin to go nuts. Try every electrical item including the radio if one item does not work that may be your culprit. But even when found if you disconnect the item then most of the other systems should start to work normally. The other thing is get a volt meter and check the battery voltage and make sure its 13.8 to 14v if its below 12 or over 14.5 then there is a problem. Normal scanner will tell you engine codes but not the rest of the body problems. But at least if you look of the engine codes it may give you a hint as to what is wrong. The lack of smooth running and variation in speed can be a ignition coil, power problem, can bus problem, fuel problem and all can be caused by voltage to high or low. Also I am assuming the battery is in good condition since it seems to crank for awhile. 

 Cars today use this can bus system because there is less and less direct contact with the item you want to turn on or off. when you switch on your headlights you move the switch into the on position, which sends a signal to the front sam (signal acquisition module) that in turn sends a signal to the headlight module. Then the headlight module switches on the power if the requirements are met to the headlight. If your headlight does not work it could cost 1550 to 2k to fix it if its more than a bulb.

[f6john]

  I've never owned one but some of my family have. Their observation, "Good cars up to 75k miles, then all bets are off." So they quit buying them.  From your experience, it sounds like you got a better than average service so far.

[Marinakorp]

Yes,

Usually this gind of electrical gremlins (multiple separate systems) point to the battery / ground.

I had a 540iT that had a mind of it's own...

New battery made it better... and then we found the bad ground that cured it of all it's bad habits.

[dpcarson]

Thanks guys.  Checked the voltage this morning and it was sitting at 12.23.  I am guessing that is just slightly low.  I also did not check the regulator voltage output this morning but after hours of reading and asking, the general consensus has been that it is battery or voltage related.  Since my mechanic is closed on weekends, all I had to do all weekend is to aggravate everybody else with questions.  Thanks for your answers.

[Big Rig]

Sounds like low/old battery...funny or as impossible as it seems...if you know or have a favorite mechanic ask him to let you "try" a newer battery. You will also have a short some where, you will just need to find it...

best of luck. 

[Jack]

I have owned a '99 BMW Z3 and, now, have a '01 BMW Z3.  Never any major problems(knock on wood).  My wife had a 2011 BMW 328i and it was in shop every few months with one thing or another.  18 months and she spent almost $2000 in repairs.  She just traded for a Honda Accord which would make her 4th Honda.  She has never had problems with Honda.

I feel your pain.

[mrtappan]

Sounds like low voltage to me.  Typically when computer controlled vehicles lose voltage they start throwing all the warning lights because each system isn't getting the signal it's happy about and thinks something is wrong.

I had 2004 330ci.  I never had that particular problem with mine but at around 150k basically the whole interior fell apart.

[doubletee]

I've had 3 BMWs since 1993. They can get really weird if the battery is in poor shape. Sounds like you've already decided to pursue that angle first, but if not, it's the place I'd start.