C5 air filter shock!

[milleplod]

When I first bought my '09 2.0HDi, I was very impressed with its service history - nice and detailed, invoices included, stamps in the book etc. Its a one-previous-owner car with 75k miles recorded - the guy I bought it from had had it dealer-serviced till it was 3 years old, then used a local garage. According to the history, it was last serviced around 10k miles ago, and this had included the usual oil and filters. Over the last 6/8 weeks, Ive noticed a noise! Bit hard to describe, but a sort of 'flat' drone when accelerating from lower speeds. It reminded me very much of a noise our Espace IV had made when the air filter was past it - I'd thought it was some sort of plastic cover/undertray vibrating, a mate suggested a blocked air filter could make the whole airbox buzz. He was right!

Anyway, I whipped the cover off the airbox a couple of weeks ago and saw this -

Now, it does look a bit dark on this photo, but, under the bonnet, in its housing, it looked quite bright and serviceable. And no, I didn't take it out to properly examine it! So, I thought to myself, its not the air filter causing the noise, it'll be some infernal bit of plastic catching against another infernal bit of plastic that I'll never find.....

I bought a set of filters yesterday, intending to service the car this weekend...air filter included, just for the sake of it. On removing the old filter, I found this -

....and the bottom of the airbox was full of dead leaves, twigs and some sort of sandy soil, amongst other things!

The car runs so much better now!!

There's a moral there somewhere.....

Pete

[GiveMeABreak]

It's amazing what gets in there Pete - I too have had sand in the bottom of the box - I'm about 15 miles from the coast, but I guess sand on the strong coastal winds is the culprit! You've reminded me to check mine too - as they don't always replace every filter at the servicing - depends on the mileage - but when you consider that this is the only barrier in preventing all this crud getting into your engine, it's always worth changing these regularly.

[white exec]

Not at all surprised by the leaves, twigs, grit and crud under the filter. That all looks pretty normal.
What is a bit of a surprise is to see what looks like a large white flat cotton pad covering the bottom of the filter element. Usually the underside is deeply concertina'd, to maximise the surface area presented to the upcoming air flow. A flat surface is very unusual. Has someone laid a sheet of cotton pad in there to keep the paper filter clean? This limited surface area would be expected to clog up much more quickly.

[Paul-R]

The filter with a pad is a heavy duty version. Underneath the pad is the standard convoluted filter.

[milleplod]

The one I took out was a Crosland....the replacement one was coincidentally the same (via ECP) and came with the same pad on the bottom.

Pete

[Paul-R]

The pad is there to filter off larger items and should last slightly longer than a filter without the pad.

[milleplod]

That makes sense, it has got quite an open 'weave' to it.

Pete

[milleplod]

It's amazing what gets in there Pete - I too have had sand in the bottom of the box - I'm about 15 miles from the coast, but I guess sand on the strong coastal winds is the culprit! You've reminded me to check mine too - as they don't always replace every filter at the servicing - depends on the mileage - but when you consider that this is the only barrier in preventing all this crud getting into your engine, it's always worth changing these regularly.

And at £5 including delivery from ECP (well, CarParts4Less via eBay), you'd have to be a real tight-**** not to!

Pete

[myglaren]

Most of my C5 air filters have been like that.

[spider]

Some of the aftermarket ones (the 406 is the same actually in this regard) do not have the extra 'foam' area they just have the normal pleated type paper.

I suspect this is because the filter type itself is very very similar to the XUD ones fitted in some vehicles...

[Paul-R]

Nah, it's just cheaper.

[spider]

Nah, it's just cheaper.

That as well

[JohnD]

I know this topic is nearly a year old but I changed my air filter this morning. I recall someone just a few weeks ago saying he'd removed his air filter to improve the running of his engine. Not a good idea! This filter has done around 12000 miles.

They are not very visible but amongst the crud there's five wasps, a couple of thistle heads and loads of grass seeds. There's an equal amount of rubbish in the bottom of the box. The new filter is alongside.

[GiveMeABreak]

Just wait to you do the pollen filter in the cabin:

Here's what I found in mine:
viewtopic.php?f=11&t=56904&hilit=pollen

[Zelandeth]

It's astonishing how much difference it can make.

The one on the van didn't look bad, so I dithered over changing it (full service usually being one of the first things I do on any vehicle when I buy it) given that they're £40 odd...must have been pretty well clogged though given how much better it runs with the new one on.

It's somewhat alarming how often you hear the stories of someone removing the filter altogether.