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Part number: 21-681C
Call For Availability: 800-299-1028
Product Details
AEM 21-681C Cold Air Intake System
Products specifications
CARB EO Number D-670
Color SILVER
Filter Color Red
Filter End Cap Finish Black
Quantity Sold as a kit.
Tube Color Gray powdercoated
Tube Material Aluminum
Clamp Material Steel
Clamp Style Regular
Clamps Included 3
Intake Pipe Color / Finish Gunmetal Gray
Product Style AEM Cold Air Intake System
Replacement Filter 21-202DK
Air Filter Color Red
Air Filter Height 5.25 in (133 mm)
Air Filter Large End Diameter 6 in (152 mm)
Air Filter Material Non-woven Synthetic
Air Filter Outlet Shape Round
Couplers Included 0
Intake Pipe Ports All intake tube ports needed for the specified applications are included
Mass Air Flow Sensor Adapter Included Mass Air Flow Sensor Adapter Included When Required
Vacuum Tubing Included No
Weight 10 lb (4.5 kg)
Case Length 20.2500
Case Height 12.2500
Case Weight 10.0000
Case Width 12.2500

AEM Cold Air Intake System relocates the filter outside the engine compartment to deliver cool air inlet temperature. Cooler air carries more oxygen, which translates into a intense explosion in the combustion chamber to create more horsepower and torque. Tuning the inlet pipe in length and diameter to match the engine's resonance helps move more air to the cylinders and this tuning allows us to deliver large power gains. It also monitors fuel trim correction factors and all OBDII sensors to eliminate leaning the engine out and throwing a check engine light. Features high standards of construction and all cold air systems include a lifetime DRYFLOW synthetic air filter and come with a limited lifetime warranty.

  • Comes with a limited lifetime warranty
  • All cold air systems include a lifetime DRYFLOW synthetic air filter
  • Features high standards of construction
  • Monitors fuel trim correction factors

C.A.S. AUDI A4, 2.0L L4, 2005-2008
Reviews
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J
Out of all the websites I've used to find my item, this was the lowest cost, and I'm so happy that I found them!  Keep up the great work guys!
H
Ordered on a Thursday evening and received my parts on Tuesday. Very quick but the website couldn't provide proper tracking info.
P
Had the product I wanted and at the lowest price. Thank you for the outstanding service!

-M
D
Great price and really fast shipping.  Great communication as well.
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Fitment
Audi A4
2008 Audi A4 ALL / Avant / Cabriolet
2007 Audi A4 ALL / Avant / Cabriolet
2006 Audi A4 ALL / Avant / Cabriolet
2005 Audi A4 ALL / Avant / Cabriolet
Audi A4 Quattro
2008 Audi A4 Quattro Avant / Base / Cabriolet
2007 Audi A4 Quattro Avant / Base / Cabriolet
2006 Audi A4 Quattro Avant / Base
2005 Audi A4 Quattro Avant / Base
Return Policy
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Not happy with a purchase? No problem. We've made returning items as easy as possible. And most purchases can be returned for free for 30 days. Learn more about our Returns Policy