Drivbiwire
Zehntes Jahr der Veteran
- Joined
- Oct 13, 1998
- Location
- Boise, Idaho
- TDI
- 2013 Passat TDI, Newmar Ventana 8.3L ISC 3945, 2016 E250 BT, 2000 Jetta TDI
The VW MAF sensor uses a microscopic heating element, any amount of oil or contamination causes the heating element to become insulated and overheats the electronic surfaces. The overheated surfaces (lack boundry layer air) distorts the microscopic surfaces. When the element overheats the airflow is distorted and the sensor can no longer provide accurate measurements of air flow.
The sensor works by taking a pre temperature reading, heats the air and takes a post temperature reading. The rise in temperature accross the back side sensor determines airflow.
K&N doesn't want you to see these:
People have NO idea how easy it is to determine how well their filter is performing.
For Mercedes they build in an electronic manometer at the MAF sensor that monitors the air filter and induction system for any restriction.
At full boost of 24 psi the air filter only imposes 3hPa of total restriction with over nearly 50,000 miles of use! The restriction data is stored in the ECU and is used to determine a filter service interval. Mercedes sets a maximum restriction value of 30 hPa for the trigger point of a filter service/replacement.
This is why I am such a strong propenent of using manometers in the OEM airbox to determine your filter change intervals.
What K&N does not tell you is that ANY amount of restriction will increase emissions, car makers cannot afford any increase and therfore design the airboxes to provide COLD AIR and no restriction to either the turbo or the engine.
A K&N can't improve on performance for the simple fact that there was no restriction to begin with. In fact the K&N simply introduces MORE dirt by virtue of its reduced filter area and larger average pore size as compared to the OEM filter that has over 10 times the total surface area. When you take into account that the OEM has more holes of a smaller diameter you quickly realize that the K&N is actually a more restrictive design when compared to the 80 deep Pleated OEM elements with a nominal 7 micron filtering capability.
After 10,000 mile of use on a K&N, note the fine dust adhering to the static charged filter box top.
Here is the MAF sensor removed from the above air box:
And here is the element, Installed brand new, Factory oiled by K&N!
(I put the dents in the filter to inspect between them)
The sensor works by taking a pre temperature reading, heats the air and takes a post temperature reading. The rise in temperature accross the back side sensor determines airflow.
K&N doesn't want you to see these:
People have NO idea how easy it is to determine how well their filter is performing.
For Mercedes they build in an electronic manometer at the MAF sensor that monitors the air filter and induction system for any restriction.
At full boost of 24 psi the air filter only imposes 3hPa of total restriction with over nearly 50,000 miles of use! The restriction data is stored in the ECU and is used to determine a filter service interval. Mercedes sets a maximum restriction value of 30 hPa for the trigger point of a filter service/replacement.
This is why I am such a strong propenent of using manometers in the OEM airbox to determine your filter change intervals.
What K&N does not tell you is that ANY amount of restriction will increase emissions, car makers cannot afford any increase and therfore design the airboxes to provide COLD AIR and no restriction to either the turbo or the engine.
A K&N can't improve on performance for the simple fact that there was no restriction to begin with. In fact the K&N simply introduces MORE dirt by virtue of its reduced filter area and larger average pore size as compared to the OEM filter that has over 10 times the total surface area. When you take into account that the OEM has more holes of a smaller diameter you quickly realize that the K&N is actually a more restrictive design when compared to the 80 deep Pleated OEM elements with a nominal 7 micron filtering capability.
After 10,000 mile of use on a K&N, note the fine dust adhering to the static charged filter box top.
Here is the MAF sensor removed from the above air box:
And here is the element, Installed brand new, Factory oiled by K&N!
(I put the dents in the filter to inspect between them)
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