Had a question about the electric power steering pump. Has anybody had a problem in cold weather with the pump taking power away from other components such as headlights? (dimming). Seems to only occur at a stop, but was worried the alternator is starting to go out at 14,500mi.

 

Mine does that too...and my garage is around 16 degrees Celsius inside. I'm just guessing it's because its an electric system. I'm no expert though.

 

I don't think it is a cold issue. I think the alternator is severly undersized. I do not have an amp, lights, mp3, radar detector... no extras to sap power and anytime any electrical item in the car is on, there's a difference in engine RPM and dimming of lights. When I turn on lights, rear defrost, radio, fan on high, there's a difference of about 100 - 200 RPM change.

 

It does seem like the alternator is undersized. Ive seen lights dim due to power windows in other vehicles, but not as much in the 3.

 

Can you even buy bigger alternators for you car?

 

I'm not an expert but ive never seen it impossible for any other car. Alternators get swapped many many times in other applications, like stereo system modifications that require lots of power. Its not always that its "bigger" but that it can put out a higher output than a factory alternator. In some cases Ive seen cars that have two alternators just because of the power crave... but in regards to this topic thats highly unnecessary. im sure a higher amp alternator can be swapped in no problem.

ive personally seen ONE instance in the just over 5 months of owning my 3 where the rpms jumped 100 to 200 rpm for a few seconds, but ive never witnessed an actual mini brownout in power anywhere in the car, and i have an aftermarket pioneer stereo with a 300w amp powering a 200w sub, a SIRIUS tuner, and iPod adapter. everything else is factory

 

Do you by chance make a lot of short trips? Sometimes the Alternator does not have a chance to recharge the battery completely and it makes the Alternator work harder, hence the dimming with the Power Steering pump usage.

 

When you"re stopped the resistancein the wheels being turned is at it"s highest.It takes much more energy than even a slow roll. If you ever drove a car that did not have power sterring you would know exactly what I mean. So of couse the lights will dim and you will be asking the alternator, and batteryto work attheir limits, or close to it. But only briefly.
I don"t see the problem.It"s still a whole lot better than putting in a mega-watt stereo system that"s beingblasted all the time.

 

BOOM TST TST TST POP TST TST TST BOOOOOOOOOOOOOOOOOOOM TSTSTSTSTSST BOOOOOP POP BOOO BOOOOMMm!!!!

 

Dang! I had to turn my monitor down for that post!