Creating a Breather Line for Honda Civic 1999 Valve Cover.




Posted in WorkshopCars

Introduction: Creating a Breather Line for Honda Civic 1999 Valve Cover.

About: As of April 2017 I have decided to no longer post on instructables. The fact that several of my published works have been removed without my consent is inexcusable. Also the insult of an author having no co...

Ever since I used a warm air intake in my car, the valve cover I let breathe via an independent air filter. In my quest for improved fuel economy, which is damn amazing thus far, I want the valve cover breathing via the engine air filter as per the original honda design.

Here is how I modified my spare cone filter to accept a breather line. The tools are;
-cone air filter.
-drill bits.
-cordless drill.
-clear pvc tubing 1/4inch OD.

Step 1: Fitting in the Breather Line.

Drilling a pilot hole followed by the final bit size, I made an entry at the base of the cone filter. I made sure to shake out all the metallic pieces from inside the cone.

I wanted the tube very snug into the hole to have an airtight seal.

Step 2: Adding to the Engine.

I popped off the existing cone filter and fitted the modified one in its place. I also removed the air filter for the valve cover. Once the modified cone filter was installed I used a length of silicone tubing to join the pvc tubing to the valve cover.

Step 3: Completion!

I started the engine and it ran well! The idle rpm was a little higher from this modification and I'm very happy about that. Hopefully my fuel economy can improve a bit in time.



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    higher idle = lower mpg at rest, though you may never notice the difference. that extra 1-200rpms is nice though during winter!

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