about them pulleys...and a few other items
I agree with Post #3 above and can add a few bits of info.
Along with the belts, absolutely do not neglect to replace the 2 pulleys on the serpentine belt. I just replaced those 2 weeks ago @ 63k miles, yet should have done so 20k mis ago. They were totally shot. Just days later, a family member's E46 325i @ 68k mis had the idler pulley seize up and break off while driving in a rural area (of course). The serpentine belt broke and immediately the car had no power steering, alternator power, and last but not least, zero coolant flow. Collateral damage in this case, probably when the belt broke, was a damaged tensioner pulley (which otherwise would only have needed the $30 pulley replaced and not the whole unit).
A good maintenance/DIY reference can be found here:
http://www.zhpmafia.com/forums/showt...e-Issues-DIY-s
Re pulleys, see item #16 on the page above and link to e46fanatics thread. Read "PART FOUR" within that post to see what happened in his particular case. His idler pulley failed at 56k mis. Resulting belt breakage damaged his water pump pulley.
There is also a tensioner on the a/c belt. Autozone sells a Duralast pulley which can be used there instead of replacing the entire tensioner unit.
At your mileage, it is advisable to do preventive cooling system replacement. You will want to do these items while the fan is out and the belts are off. This could arguably be Priority #1, given the known E46 failure points and that we are heading into summer weather.
I have a comprehensive list of cooling system replacement parts with part numbers, options for where to source, and links to more info. It's pretty much written as a note to self but I recently cleaned it up a bit after a couple other E46 owners asked for it. PM me if you want to see it. There are about 15 parts involved, the most expensive of which being the BMW-only heater/water valve ($65 from Tischer BMW). The rest can be purchased as aftermarket and or OEM parts.
As for decarbonization, use good gas with fuel injector cleaner (BMW recommends Techron by name, which is in Chevron & Texaco fuel). You might also buy some Lubro Moly Jectron and Valve Cleaner/Ventil Sauber, which you can get at bavauto.com. There is mention of this for carbon deposit reduction in the first Q&A letter in the Spring 2011 edition of their Fast Times newsletter (www.bavauto.com/newsletter/).
Bavauto also has good prices on lubricants. The Lubro Moly 0W-40 motor oil, when purchased in a 5-liter bottle plus 2 add'l liter bottles, costs about what I was paying for Mobil 1 0W-40 at Wal Mart. The Lubro Moly, however, is much better oil. They also sell Redline synthetic MTL oil for your tranny & gear oil for the diff.
I replaced the OE manual trans oil with Redline this past weekend. Easy to do (8mm hex socket for the plugs), possibly made even easier/quicker because I seem to be missing a plastic splash shield to the rear of the aluminum skid plate (?).
As for the power steering, again see page referenced above, item #22. Be sure to replace the reservoir, integrated into which is the filter. It's cheap.
I also just replaced the fuel filter, which is a little pricey (Mahle ~ $55 @ PelicanParts) due to integrated fuel pressure regulator. The only thing I'd do differently here next time is to clamp the lines and/or catch the spilled fuel into a clean container so that I could put back into the gas tank. Very sad face watching that drain out, altho probably less than half a gallon lost.
Note: once fuel filter is replaced, run the fuel pump a few times before you start the engine. I did this at a local shop's open house DIY arranged by the local BMW club chapter. One of their mechanics later went to move my car out of the shop and, not realizing I had replaced the fuel filter, did not prime the line and ended up setting off the check engine light. They cleared the code, no big deal but beware if you do this at home.
Next on my own list is a DIY on the VANOS. I plan to send mine to Dr.Vanos for rehabilitation and then use the PDF instructions on his site to do the job. It is also recommended to do spark plugs and valve cover gasket at this time, as it would otherwise be duplication of a fair amount of labor but it's nothing difficult.
The good news is you can truly do all of this, and much more, yourself. There are online DIY articles with pics & video for just about everything.
