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Fits AUDI A4 B9 (8W2, 8WC) 40 TDI
(2015)
Important compatibility info
| Function | Air Filter |
| Height | 138 mm |
| Inner diameter | 91 mm |
| Outer diameter | 174 mm |
| Type | Air Filter |
| Filter type | Filter Insert |
£11.33
Important compatibility info
| Filter type | Filter Insert |
| Inner diameter | 78 mm |
| Function | Air Filter |
| Type | Air Filter |
| Outer diameter | 177 mm |
| Height | 155 mm |
£15.96
Important compatibility info
| Weight | 0.40 kg |
| Additional Information 2 | with pre-filter |
| Height | 153 mm |
| Outer diameter | 160 mm |
| Inner diameter | 79 mm |
| Filter type | Filter Insert |
| Type | Air Filter |
| Function | Air Filter |
Additional Information
General Information
These products are designed to be used as originally intended and not modified for purpose. Please ensure the products are installed by a competent individual. N.B. products are usually supplied without fitting instructions.
£17.00
Important compatibility info
| Packaging width | 15.50 cm |
| Type | Air Filter |
| Packaging height | 18.50 cm |
| Packaging length | 18.5 cm |
| Function | Air Filter |
| Filter type | Filter Insert |
£20.64
Important compatibility info
| Outer diameter | 169.4 mm |
| Function | Air Filter |
| Filter type | Filter Insert |
| Height | 152 mm |
| Type | Air Filter |
£23.71
Important compatibility info
| Height | 155 mm |
| Inner diameter | 78 mm |
| Outer diameter | 177 mm |
| Filter type | Filter Insert |
| Type | Air Filter |
| Function | Air Filter |
£27.39
What is an air filter?
An air filter is part of the air intake system and is responsible for removing debris such as dust, leaves and other particles so that only clean air enters the engine. Clean air is essential for efficient fuel combustion however dirty air can cause expensive damage to the engine. A clean air filter can contribute to better fuel economy too. More air flow can mean less fuel us used to achieve the same power. Air filters are generally one of cheapest service parts to the increased fuel economy can lead to a filter paying for itself quite quickly.
There are three types of engine air filter:
Paper air filter
Foam air filter
Gauze (fabric) air filter
How do I choose the correct engine air filter?
Like all replacement car parts it is best to obtain the original part number and compare to make sure that you get the correct one. In situations where it is not possible to obtain a part number often the correct filter can be chosen by the following:
The W x H x D measurement of the filter
The shape of the original
Engine code
Vehicle manufacture date (this is not the date the vehicle was registered but the date it was made)
Engine number sequence (up to or after as specific number/letter
VIN (chassis number) sequence (up to or after as specific number/letter
What brand of air filter should I choose?
There are hundreds of aftermarket makers that produce engine air filters so which one should you choose. Brands such as Bosch make air filters for the original car brands however there are a good number of high quality aftermarket brands of the highest quality and meet or exceed the original specifications. Brands such as Blue Print, Febi, Borg & Beck and Napa offer quality parts that are easy on the budget. The choice is down to your brand preference or budget.
How can I tell my air filter needs replacing?
Air filters are one of the parts that should be replaced based on the vehicle manufacturers recommended service schedule. There are circumstances where you might need to change the filter before that time.
Here are some symptoms of an air filter that needs replacing:
Reduced fuel efficiency
Check engine light is illuminated
Inspection of the air filter shows it to be dirty (full of debris)
Engine misfires or struggles to accelerate
Black smoke or other harmful exhaust emissions
