2001 VW Golf 1.4 - Please explain this air intake to me?

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Thu 23 Apr 2015 12:37
2001 VW Golf 1.4 - Please explain this air intake to me? - veedoubleu

Sorry to be a pain, can someone please explain how this air intake thing works on my Golf?

I've crudely edited the photo I've uploaded it to try and make sense of it lol...

s8.postimg.org/6i042jvt1/engine.jpg

The yellow spraypaint circle shows the plastic air pipe in question, which leads to the air filter housing.

Inside this pipe is a flap (red circle position) which blocks air coming in the hole where the white arrow is.

I can push this flap down to the purple circle postion which then blocks the air coming from the green arrow tube, and vise-versa.

The pink squiggle is a long spring for this flap.

My question is what moves this flap? There's no electrics in there, no mechanism. Just a flap forced in the up position by this long spring.

Also why does this flap block anything at all?

Cheers. And I feel like I have to keep apologising on here for asking such amateur questions lol.

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Thu 23 Apr 2015 14:05
2001 VW Golf 1.4 - Please explain this air intake to me? - Wackyracer

The flap is operated by the spring mechanism(there maybe a hidden wax capsule unit). This unit will draw air from around the exhaust manifold when the engine is cold, when the air in the duct reaches a certain temperature the spring mechanism will move the flap toward the normal inlet which will draw in cooler air.

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Sat 25 Apr 2015 17:06
2001 VW Golf 1.4 - Please explain this air intake to me? - Railroad.
Carburettor icing was always a problem on older cars. Driven around town this problem would almost never present itself, but on a cold winter's morning on the open road at 70mph cold air drawn through the air intake would cause ice to form in the carburettor venturi thus restricting air and fuel flow causing the engine to cut out. After 10 minutes the ice would thaw and the engine would start and run again. The driver would report this to his garage who would look at the car and never find fault with it. Hardly surprising since they could never recreate it. The solution to this was to add a warm air intake, where intake air was taken off the hot exhaust manifold. Early cars had a manual lever on the air intake which moved a flap for summer and winter positions. Later ones were more sophisticated with a temperature controlled system.

Despite your engine being fuel injection the principal is the same. It's to prevent ice forming on the injector nozzles.

Edited by Railroad. on 25/04/2015 at 17:13

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Sat 25 Apr 2015 18:20
2001 VW Golf 1.4 - Please explain this air intake to me? - bathtub tom

Not just cold, you needed moisture too.

The only times I experienced carburettor icing was when it was damp, foggy or near water.

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Sat 25 Apr 2015 20:36
2001 VW Golf 1.4 - Please explain this air intake to me? - Railroad.
I attended plenty when I was an AA Patrol. And in all different areas too, but nearly always on rural dual carriageways and motorways where people drove at higher speeds.
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Tue 28 Apr 2015 22:04
2001 VW Golf 1.4 - Please explain this air intake to me? - veedoubleu

Thanks for the replies, I understand this now! Cheers for the help :-)

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