W210 intake vent blocked?

[wongl]

Whilst washing the car today I notice that air-inlet vent on the bonnet was collecting water (on the passenger side). It looks like it is blocked, but the driver's side is okay.

Any one knows how to unblock the passenger's side (or does it drain off the driver's side on the W210 facelift)?

 

[Dieselman]

It drains to the drivers side. You probably just filled it with the hose..

 

[wongl]

It drains to the drivers side. You probably just filled it with the hose..

Yes I did as I noticed a lot of old (pine) leaves floating out when I pointed the hose at the vent.

However when I opended the bonnet, a lot of water came gashing out of the vent onto the screen. It looks like the water did not drain towards the drivers side after all.

Maybe there is a blockage to the driver side?

How do I take this vent apart to investigate?

 

[PhilL]

I have a pre-facelift W210 Estate but I assume it's the same as yours.

If you raise the bonnet and look on the underside of the plastic vent on the drivers side you should see a small drain, about 20mm across, with a plastic flap. This normally allows water to drain from the bonnet into a small collection trap and into the drains at the rear of the engine bay.

open the flap and clean out the drain with a small screwdriver.

I did mine yesterday and although it was not fully blocked a lot of dirt and dust came out.

 

[wongl]

I have a pre-facelift W210 Estate but I assume it's the same as yours.

If you raise the bonnet and look on the underside of the plastic vent on the drivers side you should see a small drain, about 20mm across, with a plastic flap. This normally allows water to drain from the bonnet into a small collection trap and into the drains at the rear of the engine bay.

open the flap and clean out the drain with a small screwdriver.

I did mine yesterday and although it was not fully blocked a lot of dirt and dust came out.

Many thanks for this. I did the same already and was surprised that this did not clear the passenger side. I think I need to take the vents of to give them a proper cleaning! I also noted that the passenger side drainage (from the "wiper grill" - drains below the wheel arch) was completely blocked with "pine needle" too. It too a lot of poking and prodding to clear this blockage. I suspect that this is also the cause of the blockage in the vents.

 

[wongl]

Blockage cleared

Okay, managed to clear the blockage by removing the vents and reverse flushing them. Seems like a design flaw to me as the drainage channels for the passenger side is no more than a couple of mm which seems to be prone to blockage see photo.

First photo is the air vent with the "lower drainage box" reomoved (this is held by a single screw on each side and 7 clips along the top). The air vent is held in by 7 screws.

Second photo shows a close up of the blockage (underside of the vents). It took me quite a while to remove the blockage of "pine needles" using a hosepipe and a straighten paper clip!

Finally took the opportunity to clean all that black plastic with Autoglym plastic restorer (see last photo) before refitting the parts back to my car.

 

[Dieselman]

Top job, well done. Thanks for posting that.

 

[PhilL]

As they say "A picture paints a thousand words" so now all is clear. The Autoglym plastic restorer looks to have done a fantastic job; I've not tried it myself but must add it to my collection.

Another job for the Weekend!