K&N Air Cleaner System

GR8_ASP

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Just installed the K&N air cleaner system. Overall everything went smooth. Very straight forward and reasonably good instructions. However, when I went for a test drive I heard a strange high pitch sound coming from the engine region. Loudest during decels and idling. Anyway, to make a moderate story short I determined that the PCV make-up air ****** on the inlet tube was overly restriced causing the crankcase to operate at too much vacuum. The high vacuum caused the PCV valves to whistle like crazy. So advice to anyone with the K&N's is to check each ****** (there are only 2) to make sure that the hole is open all the way through. Mine was flashed over with about 1 mm thick flash near the inside opening. Required drilling to open it up. Once cleared it worked perfectly.

Another improvement I made is creating a seal along the back edge using sealed foam tape. The gap was almost 1/4 inch and I did not want hot engine compartment air entering. Seems to seal well and directionally correct. I won't claim any hp advantage and start a whole new Vipair discussion :)
 

JonB

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Just installed the K&N air cleaner system. Overall everything went smooth. Very straight forward and reasonably good instructions. However, when I went for a test drive I heard a strange high pitch sound coming from the engine region. Loudest during decels and idling. Anyway, to make a moderate story short I determined that the PCV make-up air ****** on the inlet tube was overly restriced causing the crankcase to operate at too much vacuum. The high vacuum caused the PCV valves to whistle like crazy. So advice to anyone with the K&N's is to check each ****** (there are only 2) to make sure that the hole is open all the way through. Mine was flashed over with about 1 mm thick flash near the inside opening. Required drilling to open it up. Once cleared it worked perfectly.

Another improvement I made is creating a seal along the back edge using sealed foam tape. The gap was almost 1/4 inch and I did not want hot engine compartment air entering. Seems to seal well and directionally correct. I won't claim any hp advantage and start a whole new Vipair discussion :)

GREAT ADVICE We will share with K+N the quality control issue of the ****** flashing. And thanks for buying this kit from us Ron !
 
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