K&N Air Filter for new 2009 TDI?

I can't seem to find a K&N Air Filter for my 2009 Jetta TDI. I found some 2008 2.0L Air Filters. Not sure it's for a diesel. Does anyone have any insight?

Thanks in advance!

Alex

K&n

I can tell your a newbie because you did not do a search on K&N air filters. A K&N air filter or any oiled air filter will ruin your MAF! MAF cost $$$. Void your Warranty! Does no improvement to a TDI. Do a search and you will find the facts. The original paper filter does an outstanding job!

BOSTON-VW said:

I can't seem to find a K&N Air Filter for my 2009 Jetta TDI. I found some 2008 2.0L Air Filters. Not sure it's for a diesel. Does anyone have any insight?

Thanks in advance!

Alex

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You are lucky. They are known for damaging your MAF. Unless you have made some serious modifications, you will not gain any additional power or mileage using one, but you will risk damage. Don't use K&N air filters. (Note this advice only applies to the more common oiled versions.)

2004STARWARSTDI said:

I can tell your a newbie because you did not do a search on K&N air filters. A K&N air filter or any oiled air filter will ruin your MAF! MAF cost $$$. Void your Warranty! Does no improvement to a TDI. Do a search and you will find the facts. The original paper filter does an outstanding job!

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Yes...You're correct! I'm a total newbie! Thanks for setting me straight the both of you! I'm glad I asked! I'm digging my new Jetta TDI. Getting use to the diesel in general. The 6-Speed isn't like my 2003 GLI at all. I like it just the same.

In your defense, "K&N" does not work as a search term, my guess is because of the "&".

starwars.....easy man......get some decaf.....

Yes, they are correct. They do ruin the MAF, just like any VW would be affected. The bigger issue is the fine particles that get past the filter and sand blast the turbo vanes. I've seen them worn down 10% and that car made NO boost.

2004STARWARSTDI said:

I can tell your a newbie because you did not do a search on K&N air filters. A K&N air filter or any oiled air filter will ruin your MAF! MAF cost $$$. Void your Warranty! Does no improvement to a TDI. Do a search and you will find the facts. The original paper filter does an outstanding job!

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Hey, don't get hysterical! I've had a K&N on my Hyundai for the past 30K miles, and it works just fine. No problems with the MAF sensor either.

However, I wouldn't get one on a TDI, because (just like with any turbocharged engine) the turbo compresses the intake air to a constant pressure regardless of how restrictive the filter is (within reason, of course).

The bigger reason to not get a K&N in my view - aside from that the performance benefit will be nil - is that it removes an excuse for the VW dealer to blame YOU, in the event that you have a situation that requires a warranty claim.

Back in the dark days of Mk4 MAF sensor problems, many a MAF sensor claim was denied, rightly or wrongly, because the dealer pointed to a K&N filter and said "That is the problem! YOU caused this! Pay up!"

Stock air filter ... they can't say that.

mrchaotica said:

Hey, don't get hysterical! I've had a K&N on my Hyundai for the past 30K miles, and it works just fine. No problems with the MAF sensor either.

However, I wouldn't get one on a TDI, because (just like with any turbocharged engine) the turbo compresses the intake air to a constant pressure regardless of how restrictive the filter is (within reason, of course).

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Don't forget that because a diesel engine is a very high compression engine, it sucks in far more air than a gas engine does. The little bit of oil mist coming in on a gas engine may not damage the MAF, but the more air that comes in, the more oil mist comes in too.

To the OP, I wouldn't mod anything at all until the warranty runs out. Owners have a hard enough time getting warranty work covered as it is. Any mods at all will give them an excuse for denying an otherwise legit claim. This is especially true of fluids. Use ONLY factory specified oil, coolant, PS fluid, etc. even after your warranty runs out!!

learnin' is a good thang

glad I read this thread. I have ALWAYS used K&N in my American cars, and in the old gasoline 70's veedubs I drove back then. Tho it makes sense not to use them in the TDI,
after what I have learned here.

So - is there a high(er) performance air filter for the TDI?

I'll give my personal experience for this thread. When I bought my TDI it already had a K&N filter in it from the previous owner. At that time I didn't know that it was a bad thing. Anyway since it was already there I didn't thing that my TDI was slow or gutless but when I had Kerma tell me that my MAF was toast I bought a new one along with a new air filter. Now my car is so much better than when I bought it.

The factory air filter flows way more air than the can can ever use.

jasonTDI said:

The factory air filter flows way more air than the can can ever use.

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Internet studder!

I dont feel like arguing, so... the factory crap paper filter outflows any performance filter.

Using a K&N filter will cause the large hadron collider to malfunction, creating a black hole which will surely kill us all.

velociT said:

Internet studder!

I dont feel like arguing, so... the factory crap paper filter outflows any performance filter.

Using a K&N filter will cause the large hadron collider to malfunction, creating a black hole which will surely kill us all.

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It doesn't have to outflow 'any performance filter'.

It just has to outflow the damn engine. Which it apparently does with ease.

What is so hard about this concept?

It is not rocket science....

Bill

velociT said:

Internet studder!

I dont feel like arguing, so... the factory crap paper filter outflows any performance filter.

Using a K&N filter will cause the large hadron collider to malfunction, creating a black hole which will surely kill us all.

Click to expand...

We have the same air filters used in the 1.8T and both VR6s (2.8L and 3.2L). I suspect they pull much more CFM than our TDIs. THAT is the point folks are trying to make. The OEM filter far exceeds the needs of our engine. Folks making over 300 ft-lb and 200 HP are using the stock air filter

It appears you are used to gasoline engines with crappy OEM filters. TDIs and VW OEM filters are neither.

That is the important point. When the OEM filter is better than needed, replacing it with something else will only result in the same results or less. It won't make it better.

I won't argue. It's fact that the car cannot use more air than the paper filter can provide. The K&N and ANY other filter don't do an adequate filtration job. Period. NO horsepower gains, dyno proven. It's not a racing motorcycle......You haven't been around here nearly long enough to see the test that were preformed with flow rates and filtration.

Why does the rally car run a paper filter then? Hmmmm.....maybe because it flows and FILTERS.

K&N is fine in a motor you REBUILD every 500 miles. But ANY professional team I know runs quality paper to keep the debris out and durability IN.

velociT said:

Internet studder!

I dont feel like arguing, so... the factory crap paper filter outflows any performance filter.

Using a K&N filter will cause the large hadron collider to malfunction, creating a black hole which will surely kill us all.

Click to expand...

You know what I think is funny? If all cars came factory stock with a K&N filter, all the modders would be switching to paper filters just to be different from stock.

Nothing more annoying than K&N fanboys at the local autozone raving about how they got 10 more hp and 5mpg.

If you want more flow, or just to feel like you have more flow, upgrade the airbox/intake tubing, snorkel, etc.

Revolutionary_mind said:

Nothing more annoying than K&N fanboys at the local autozone raving about how they got 10 more hp and 5mpg.

If you want more flow, or just to feel like you have more flow, upgrade the airbox/intake tubing, snorkel, etc.

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I just got done removing the stock airbox-filter assembley on my 2009 sportwagen and fabricated a new intake tube -highflow washable filter. I went light on the oil for the filter. The differance is absolutely amazing. I feel like I picked up 50 hp. The car requires much less throttle application than with the stock airbox. This is a must do mod. I cracked a smile I could not wipe off during the 1st roadtest. I will advise of mpg +/- in the next couple of days. You doomsayers know not what you speak of.

MAF failure in 3... 2... 1...

Seriously, it's sad how many people have to actually have a failure happen to themself before they believe it.

I run about 15,000 miles a month . I am about to turn 20K on my 09 already so it should not take long for my MAF to fail if its going to. BTW get some MAF cleaner and spritz it off every other oil change...Go light on the filter oil.

40X40 said:

It doesn't have to outflow 'any performance filter'.

It just has to outflow the damn engine. Which it apparently does with ease.

What is so hard about this concept?

It is not rocket science....

Bill

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It's Rocket Surgery. Sorry. I Couldn't resist. Continue.

Although, I agree with the K&N being crap (the oiled ones), I do believe that the AEM Dry Filter is a very good filter. By just looking at the intake piping of the AEM compared to the squished down piping of the stock, I would say it has to flow more air, but if the stock already "outflows the damn engine", then maybe more air would just be money wasted.

I don't really know either way performance wise, but I do know that the AEM clears up a lot of space under the hood.

-Brian

Brian.Burress said:

It's Rocket Surgery. Sorry. I Couldn't resist. Continue.

Although, I agree with the K&N being crap (the oiled ones), I do believe that the AEM Dry Filter is a very good filter. By just looking at the intake piping of the AEM compared to the squished down piping of the stock, I would say it has to flow more air, but if the stock already "outflows the damn engine", then maybe more air would just be money wasted.

-Brian

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Paper filter fanboys in 3..... 2..... 1......

Perhaps there is a reason why folks who *race* TDIs (Jetta-girl, IBW, the Rally Car are some) don't use K&Ns.

LILALLEYKATT said:

(snip) Go light on the filter oil.

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__. That's a *perfect* recommendation. It's the oil that catches the abrasive dirt particles. A K&N already lets a LOT more dirt through the filter than paper ... yeah, cut down on the oil. Make a poor filter even worse. What kind of critical thinking is going on here???????

__. (Yeah, I know -- there is NO critical thinking going on here.)

Forgive me, but I've always thought that a free-flow air filter was used primarily for hi-rev engines to help breathability at the top end. Why would it be needed for an engine that only revs to 5K? And turbocharged at that?

Confused...

Really?

We do actually. More Specifically, I do. I work on these every day. I'd like to see some dyno numbers please....Granted you shortened the intake length but the feel is more than likely the noise you picked up. Hey, um.....have fun with the instant warranty denial.....Ya'll can't believe everything you see on Horsepower TV. T'aint 'merican V8.

LILALLEYKATT said:

I just got done removing the stock airbox-filter assembley on my 2009 sportwagen and fabricated a new intake tube -highflow washable filter. I went light on the oil for the filter. The differance is absolutely amazing. I feel like I picked up 50 hp. The car requires much less throttle application than with the stock airbox. This is a must do mod. I cracked a smile I could not wipe off during the 1st roadtest. I will advise of mpg +/- in the next couple of days. You doomsayers know not what you speak of.

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For those of you who do not know the background of K&N; In the 60's and 70's, Off road Motorcycles came with paper elements. When they were ridden and raced in dusty environments like Baja for example the air filter would clog in short order. K&N made a fortune with their new filter which wouldn't clog anywhere near as fast as a paper element. It also flowed quite a bit of dirt as well as air.
Now back then it was common for an engine to be torn down after every race so the increased wear and dirt in the engine wasn't noticed as much. In the mid-late 70's the Motorcycle manufacturers did extensive testing and found that oiled foam elements kept the engines far cleaner than a K&N while flowing nearly as much air. They also didn't clog as easily as a paper element. Since they are now standard equipment on pretty much every off road Motorcycle and ATV this cut heavily into K&N's market. Thus they entered first the street bike market (K&N Jet Kits) and a few years ago the car market.

Do they flow better than a stock paper element? Yes.
Do they filter better than a stock paper element? No, not even close.
What is the best filter? Probably an oiled foam or perhaps a synthetic media filter. Paper does a great job though on a street engine and on most race engines.

Unless an engine is starving for air due to a bad airbox design, increasing the airflow in without increasing the airflow out and the fuel will have a negligible effect on performance. An engine only needs as much air as it needs for any given throttle opening. Everything must work together to get max performance and mileage.

Use what you want though. It is your money.

Turbo motors draw a LOT of air FWIW.

ToolNut said:

Forgive me, but I've always thought that a free-flow air filter was used primarily for hi-rev engines to help breathability at the top end. Why would it be needed for an engine that only revs to 5K? And turbocharged at that?

Confused...

Click to expand...