Can yo uhelp me locate the Cabin Air Filter in my 2001 BMW 530i?

there isn't a cabin air filter on a 2001 Tacoma.

If a coil was bad, it would be missing or misfiring. Could be a clogged filter or a weak fuel pump. To check have the fuel pressure tested. If pressure is good, a tune-up might help.

Check behind the glove box if u fold down door and look in it should be there

Dust & pollen cabin air filter location:

By the passenger foot location. Check web on exact replacement procedure.

• Refer to your owner’s manual for the specific location of your cabin air filter. Some are found in the engine compartment and others are located in the interior of your car, under the dash. Note that some models may have more than one cabin air filter, so be sure to check both and replace them when needed. We suggest replacing them in pairs to eliminate the hassle of future occurrences.
• Loosen the box and inspect the cabin air filter for debris, dirt, leaves and other objects that are obstructing the path of air entering the cabin.
• Remove your old filter, clean the filter box and install a new filter. Secure the box.
• Run the A/C systems with the doors closed to verify the repairs.

It will either be behind your glove box, or will be located under your hood by the firewall.

Behind the Glove Compartment
1. Open the glove compartment and remove all the items from inside of it.
   
2. Remove the glove compartment assembly retainer screws with a Phillips head screwdriver. Refer to the repair manual for your specific year and model series BMW for the exact location of the screws or carefully look around the perimeter of the interior glove box assembly to locate the screws.
   
3. Locate the lower trim panel retaining screws behind the glove box assembly. Remove the screws with a Phillips head screwdriver and then remove the panel.
   
4. Remove the foot-well air duct.
   
5. Loosen the retaining screws of the control module box to all you to lower it down.
   
6. Turn the cabin air filter panel retaining knob counterclockwise to open the panel. Pull the filter removal tab outward to remove the filter.
   
7. Use a shop vac to clean out any noticeable debris from the cabin air filter housing interior.
   
8. Insert the new filter and reverse the order to reassemble the foot-well air duct, the trim panel and the glove compartment assembly.
   
Under the Hood
9. Open the hood and locate the cabin air filter housing. The housing is located near the cowling on the top section of the firewall. Some models place the housing in the middle of the cowling, on both sides--left and right--of the cowling or on the passenger side cowling. Removal of the cowling and placing the windshield wipers in the upward position may also be required on certain models. Some 7-Series BMWs place the filter housings on both the left and right side undercarriage of the hood.
   
10. Release the cabin air filter duct clamp. This can either be released by unclipping the air filter duct by pressing a retaining lock with your fingers or using a flathead screwdriver to pry off a retaining rod.
    
11. Lift the cover upward--or downward on hood-installed 7-Series BMWs--to reveal the cabin air filter.
    
12. Remove the cabin air filter from the air duct. Vacuum the air duct with a shop vac.
    
13. Insert the new cabin air filter(s) and reassemble.
    

abs control module is bad

If its a 96-05 then its under the hood near the back of the engine compartment. You twist the 3 plastic clips 90 degrees and it comes off. Then replace the filter.

actually just unlpug all the hoses and take any thing than is on the way to remove it, then afer you replace it, some over flow bottles for the cooling systems have, a little plastic bolt by the cooling system cap have the bolt loose while you fill it with coolant and then it will remove any air trap on the cooling system then tie the bolt when system is full and place the cap on.