Alternator Issue?

[bignasty27]

Hi Guys,

Finally found an X5 2005 4.4 that I liked and with a great price. Pulled the trigger and here I am a month later.
I am getting used to everything about a BMW since this is my first.

Ive noticed a few things during that month. When I first start it everything is great and sounds great. Driving away, I can feel the gears switching from first to second etc. Nothing excessive but I can feel it. No kick or anything. Maybe its just me cuz Ive gone from a Jeep to a Bmw and in my head, I shouldnt feel anything.

The MPG gauge, when driving, doest always react to how I am driving. For example, when coming to a stop, the gauge will seem to get stuck at 10. Even a complete stop it sometimes get stuck at 10. After driving away again, the MPG will be normal and act as it should with readings going down to zero. The gauge operates normally after driving around for 10mins or so. It seems it takes time for everything to warm up.
After the truck is warm ( 10 minute drive ) the gears are seamless when switching.
Do all BMWs need time to warm up? Its not exactly cold right now outside either, around 60 degrees.

Few days ago, I started to get a chirp, squeal when I started it up coming from the alternator area. The noise goes away after driving for a few mins. The noise is here one day and gone the next so I havent gotten it checked out.

This truck sat for a couple of days and when I went to start it this morning, it started but was a rough start with it shaking like it was about to stall. I turned it off and restarted it without any issues and drove to work. No problem. Took it out at lunch and again, no issue.

There is also a slight hum that I can hear in the cabin, almost like a speaker hum but the radio is off and Ive never touched the speakers or installed any new radio equipment. It is not coming from the speakers but I do hear a hum.

My question is, does this sound like an alternator issue?

Not sure of the service records of the truck but it is in great shape, had it checked out by a mechanic before the purchase and all was clean.

I have 100,000 kms on it which is appprox 62000 miles.

Any thoughts??

[Yii]

Usually clues with bad alternator is the dash being lit up like a Christmas tree. Do you have anything like that besides the noise? Maybe the belt is about to go? i replaced mine later in mileage but your car is 8 years old now, I'd also recommend you change your battery since again its 8 years old and usually these beast sucks the battery dead.

[bignasty27]

The dash did not light up at all. Everything was fine except for the check engine light flashing along with the other lights on the dash when it seemed like it was going to stall.
I will try the changing the battery and the belt and have the alternator tested anyways.

Anyone else have any ideas?

[upallnight]

Check engine light on or flashing could be a DTC (Diagnostic Trouble Code). Normally you can get an OBDII to read the code(s) since the truck is OBD II compliant. I use a bluetooth scanner in conjunction with an app called Torque on my Android phone.

[bignasty27]

The check engine light never actually stayed on. It flashed during the rough start but that was only about 2 seconds till I turned off the truck. It hasnt come on at all for the month I have owned the truck. The truck has started perfectly ever since.
Looking to get rid of the chirpping sound that appears every 4th day or sowhen I start it up and disappears when after I drive away.
Will try battery and belt.

What type of battery are people using aside from the BMW dealer battery?