Random lack of power...MAF? K&N? What's this?

Barbel12

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Hi

I am posting on behalf of my mate who own a 2001 Audi A3 1.8T, he had a K&N 57i Kit installed a little while ago (really badly) and since then it's been running very randomly. It will be fine for a day or two then it run poorly and while driving has a complete lack of power.

I cleaned the MAF sensor today and refitted the K&N and also installed some new spark plugs and did an oil change I also cleaned the little sensor that sits behind the Throttle Body. Since doing this it seems to be running ok but only time will tell. Does this sound like a MAF issue?

Can someone tell me exactly how a K&N 57i kit should be fitted properly? I feel as though there should be more cold air being sent directly to it and also blocked off more from the engine bay.

Also please see attached photo, I'm not sure what this is or how it got damaged but wondered if it's a critical fix? Just seen it needs to be a hosted photo, it's basically a small black unit that sits behind the washer bottle on the left side. I'm sure it's fuel related but can't find an engine diagram online to assist.

One last question in terms of performance tweaks, what do you recommend? Engine Remap? Silicon Pipes? Turbo tweak?

CHeers

P
 
the small black box you mentioned is the charcoal chamber, im assuming you think its broken because it makes a ticking noise? well thats normal mate, cant tell you exactly what it does as i dont know myself, trying doing a search of the forum, theres bound to be a thread on it somewhere

to test the maf, unplug it and go for a drive, if the car is noticeably better then the maf is ********, if replacing only use genuine audi part, not cheapo's off ebay as you will only be replacing it again a few months down the road
 
iirc the k&N 57i is an oiled filter. there is light coating of oil on the cone that helps all the crud sick to the filter. there a bit cack in me opinion. oiled filters kill mafs simples. and a K&N has got to be the worst filter ever to put on a car. there poopie. General rule of thumb, if halfords sell it its shat! (when it comes to "performance parts anyway") Heat soak will also add to the overall lack of performance as i said before.
 
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I wouldnt be too sure it is the K n N, as ive had one on mine from new with absolutely no problems at all! my car was running rough on and off a while back, it was due to a very small crack in one of the breathers pipes. have a closer inspection u may find u have the same problem!
 
may well not be the K&N as you say... im just going from past experience. if you compare a k&n to other filters you would kick ya self for not buying another make. i think im bias.... i hate k&n
 
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A dodgy MAF ia a likely cause as are vaccum leaks, if it were my car I'd refit the standard airbox and see if that helps as Alpine says Heat Soak is a likely cause, the other thing I would definately recommend is scanning it first with VAG-COM for fault codes. Hope this helps and good luck, keep us posted
 
Thanks for the info chaps....

I'm thinking one issue with the K&N is that it's installed directly into the MAF chamber which can't be good for either cold air (as close to the engine) and that oil getting into the MAF.

Would a Silicone or Alu extension tube benefit this setup by moving the actual filter further away?

By next question other than the basic servicing I've already done...sparks, oil, oil filter, MAF clean, Sensor behind throttle body clean is there any other good service ideas for this engine?

Going to look for a local VAGCOM test centre in Berkshire....any ideas?

Basically once the engine is running well he wants to get a remap, can anyone recommend a good place to go?

Thanks

J
 
Also meant to ask more about this "charcoal chamber" I can't find anything online about it?? Basically there are two connections going into it and the back one is damaged somehow.
 
Try searching charcoal filters on cars. It is fitted to some cars for emissions purposes. A vacuum line draws the fuel tank fumes through the charcoal filter which seperates the suspended fuel from the gas. The fuel then returns to the tank, and the gas is drawn into the TIP or throttle body.
 
Right well the car is playing up again, same as before with the MAF connected it's running strangely.

Would a replacement MAF sensor fix this or could it be something else? If I change the MAF is this likely to keep happening because of the K&N?

Will running the car for now without the MAF cause any issues? Where can I buy a replacement?
 
Until you have done a thorough check using VAG-COM there is no point simply changing parts at random unless they are know to be iffy, as my earlier post said it COULD be your MAF but it could be a number of other things. If you still have the origional airbox and filter, refit the thing and see how the car runs, then run VAGOM and go from there. On all the 1.8T engines there are so many issues that can cause problems it's a nightmare to find them but you need to do the diagnostic process in a sensible way.
 
Cheers guys, I took a punt and first ditched the K&N for the original air box filter but it still didn't work so I got a new MAF and it's now working like a dream! So next question is what panel filter would be good.....??? Also now the car seems to running well I'm going to get a VAG COM done (thanks Alpine might take you up on your offer).

What remap/tuning would you recommend?