Servicing question - K&N Filter

[karachi_kops]

Hi Guys

Im just after some advice. My Audi A4 1.9 Tdi is due a service which im hoping to carry out in the next few weeks. Im considering replacing the normal Air Filter with a K&N Panel Filter. Would this be a good investment? Or am i asking for trouble?

Also with regards to the service, how often would you need to change the Glow Plugs? Apart from the Oil and filters, would i need to be looking elsewhere? Brakes are starting to squeak but seem to be ok so far.



Karachi Kops

[ibsey]

Hi Guys

Im just after some advice. My Audi A4 1.9 Tdi is due a service which im hoping to carry out in the next few weeks. Im considering replacing the normal Air Filter with a K&N Panel Filter. Would this be a good investment? Or am i asking for trouble?

Also with regards to the service, how often would you need to change the Glow Plugs? Apart from the Oil and filters, would i need to be looking elsewhere? Brakes are starting to squeak but seem to be ok so far.



Karachi Kops
am no expert but for years have been led to believe K&N filters are a good upgrade, no personal experience to date!! with brakes when i change them i always put copper grease on back of pad stops squeaking, mind you dont get any on face of pads.

[Muddy19]

hi,

i'v got a 96' tdi (ahu) with k&n panel filter in there.

it is a good investment solely because you are using a quality filter. you wont really feel a big difference in performance or sound (as its a diesel), but it will feel a bit "healthier" i know am not making sense. but i've not had problems with it what so ever.

nevertheless, my MaF is bonkers anyway ( so i wudnt get any performance gains if there was to any to be had). but whatever you do, if you get one, dont ever over oil the K&n (which you should rarely have to do anyway)

for service, you may need consider the following,

oil & filter
air & pollen filter (the latter usually overlooked by many)
fuel filter
i always check my fan belt also as this has snapped twice (once because of a retarded mechenic, and once probably my fault for driving at 120 (k/ph of course - wink)

If you want to, do a diagnostics to see if your're Maf or EGR are playing up. you may also want to use a qualtiy engine cleaning thing (you add it to your oil, run the car at fast idle and it drains the junk with your oil - apparnetly) - sorry, i dont know what its called.

with regards to glow plugs, mine were done by audi at 80,000 miles and the car is now on 170,400miles and starts first time, everytime regardless of snow or sun. - that is if the immobliser is not playing up ( doesnt mean they havnrt been changed tho) - i would advise you to leave them until you get hesitation/problems starting in the morning.

by the way, get your brakes checked out. them and tires might the only thing between you and hell (or heaven). (dont get mintex pads as they are too thick, and after hours of grinding and bashing to make them fit, they just get your calipers to stick! - believe me, i know....)

[A4Chris]

My advice would be to stick with the standard factory fit type paper element.

Being oil coated, the K+N filters can destroy MAF sensors which are very sensitive to oil contamination (therefore a bad idea to stick an oil based filter directly upstream of the MAF in the intake system).

If you simply don't oil the K+N filter then it won't be working as a filter and you may as well have nothing in there! (the K+N filter works by trapping dust / particles in the oil which coats the gauze). Without the oil coating then dust and particles can get into the intake system and this is bad news - especially with a turbocharged car. The particles will knacker the turbo vanes if they enter it when its spinng at a high RPM.

With regards power increases etc... you will notice bugger all in a diesel by fitting a K+N. If you must fit a 'long life' filter then go for a foam one such as Pipercross. However foam filters can be more restrictive than paper and hence you may loose a little power with a foam filter.

I would always say keep it the way the factory made it and stick with a standard paper filter!!

[Muddy19]

well chris is right. K&n is oil based. and that is not good for your MAF.

personally i stuck one in, and the wernt any worse problems than before. my car used to overboost a lot, ( and then oodles of turbo lag) but i cleaned my maf out. apparantly thats also a no-no but its alright now in my car. (the only issue worth noting it slows down a bit on motorway uphill) - maybe thats kaz my maf is still buggerred, or because the engine is 170,000mile old.

its true whats chris is saying, oil based k&n is not good for your maf (especially when over oiled). but iv had the k&n in there about 15,000miles ( i do about 20-25k a year) and iv not had any problems with the turbo (fingers crossed).

its up to you. chris is the sensiable voice. all am saying, iv got one. and theres no big difference (that i know of) but k&n are in general good filters.

[karachi_kops]

Hi A4Chris and Muddy19

Thanks for your posts :o)

I didnt think i would notice much difference by placing an oil based filter in, plus with the damage it can cause to the MAF sensor would be best to avoid this idea!
I think i will stick to the normal factory fixtures but thought id see what everyone thought to the idea.

Im hoping to buy all the servicing parts by the weekend.

One last question, if i may, with regards to servicing parts, how often should the glow plugs, sparks be changed?
Last year when i bouight the car i had a oil/air and coolant changed. Since then ive done 15k however i did a oil change 8k previously which is when i changed the cambelt.

your help is much appreciated ...

Karachi Kops

[Muddy19]

dont hold me to this,

but i think glow plugs are not like spark plugs. they dont need to be changed for thousands of miles ( i heard 50,000 - 80,000miles). - maybe wrong, maybe right....

my car was fully serviced by audi until 80,000miles (and thats the only time the glow plugs were changed) - but my car is special tho....lolz.

naa, dont worry bout the plugs until you get problems starting or feel that the car doesnt start properly. anyway am pretty sure glow plugs would come up in a diagnostics if there was any fault with them. personally- i say leave them if you dont have any problems with them.

[karachi_kops]

cool cheers for the post - looks like thats one less item to buy!!!

well ive not heard many ppl having to change their glow plugs so i guess that would be why lol i guess as long as the oil, oil and air filter are regularly changed, the car should be at its optimum.

Hoping to get all my brakes changed as they are starting to squeak, especially when i reverse, i get a loud sharp noise. Just a shame the rear brakes dont show up on the onboard display.

Thanks again ...

[kimandsally]

K&N filters are great as being cleanable you can be sure of peak performance all the time but you'll need to do 80,000 miles to recoup the cost.