My truck was at the dealer for 5 weeks getting new injectors and while it was there the mechanic called and left me a message that my K&N air filter was not supposed to be installed on my truck. So when I picked it up the other day the K&N was in a box in the front seat. Does anyone know if this is true, if so why?

Spiderdiesel,


GM just released a Service Bulletin saying that if a Mass Air Flow sensor fails, and a K&N or similar oiled filter is in place, that they are not going to warranty the failed MAF because of the oil on the filter is coating the MAF and causing it to fail. You should keep a stock paper filter on hand if you need to have it in service. It's BS that they're doing this, but it's true.

And before you take it in for service, clean your MAF with some alchohol..... NOT Beer.... Rubbing alchohol.... The oil collects on it for some reason...... If you oil your filter to much it with throw a code right away........


GM must have been replacing to many dirty MAF's

I been running a K&N/AFE for 45K, My brothers been running his for 35K, I did replace mine, I was getting a soft code for MAF malfunction. I dont think MAF is much of an issue until you recharge it, some people slap on alot of oil. I dont think its just a K&N issue, I think its an issue with all oiled filters.


If your truck is an 01' with the older style intake setup, their was a TSB for replacing the intake setup, and changing the MAF, As this setup allowed alot of water in, contaminating the MAF.


I will say, if you do have a MAF issue, and are running a NON stock filter, remove it when you bring it in. I think a MAF was like 100 bucks


Bill

Where is the MAF Senor.

Bill---Look right behind the Air Filter box where the big air tube hooks to the box and you will see a little black box on top of the tube, with electric wires running to it. That is the MAF.

Thanks alot that info is good to know. My truck is a 2001 w/ 90,000 miles and I put the K&N on about 15,000 and have not had a problem yet so I will probably reinstall it.

I realize I am going to touch off a huge, passion filled debate here but I "must".
From a lube engineer's perspective, the K&N air filter does a wonderful job of filtering 'bricks and birds'. Period. Anything smaller gets a free ride through your turbo-charger, then on through the system. It takes but one teaspoon of dirt to destroy a large CAT V-12 engine. Much less for our Duramax.
There is no tackifier made that will reach out and capture a dirt particle traveling at over 100 mile per hour. None. What you see when you hold the K&N up to the sun is exactly what a dirt spec sees.
Our turbocharged engines utilize a huge amount of high velocity air. The turbo will get its air wherever and restriction is not a problem. Non-filtration IS a problem; a significant one.
I highly recommend you consider either a stock AC or a Unifilter. The Unifilter has proven both excellent air flow and filtration characteristics. And no, I do NOT sell Unifilter air filters....
There, I've said my piece, standing by for the shrapnel...
George Morrison, STLE CLS

Excuse my ignorance but what is a Unifilter and where could I get one?

http://www.unifilter.com/index.htm Try this site spiderdiesel.

No shrapnel from my direction, I totally agree with George!

Any thoughts on the air filter put out by Amsoil???

There have been some quality issues with recent iterations of the Amsoil air filters. Separation of the two mediums.
The Unifilter quality is superb and the oil analysis results including particle counts/ferrography, same..
George Morrison

There have been some quality issues with recent iterations of the Amsoil air filters. Separation of the two mediums.
The Unifilter quality is superb and the oil analysis results including particle counts/ferrography, same..
George Morrison

The way the filter is trapped in the airbox, with the screen in place, not sure if that is a problem. I checked mine closely at the last cleaning and the bonding was solid. Mine is almost two years old.

I believe the Amsoil quality issues have come about with filters produced in the last year.. Fairly recent change in manufacture resulting in bond issues.
George

George is the Amsoil filters that are affected are the ones made in the last 6 months. They have a blue seal around the outside of them. This issue is suppose to be solved and as of late I have not had any returned. I will be keeping a close eye on this. Otherwise it still filters just as well as it always has. As far as the MAF goes it will be and issue with ANY oiled filter be it K&N, Uni or Amsoil.

Greg

The problem was with the ones with the blue surround:





http://www.dieselplace.com/forum/uploads/Amsoil_filter_separation.jpg





Word is that the problem is corrected, but I've moved on to Uni and a MUCH better product...

A photograph of the Uni, please..... A picture is worth a thousands words, as they say....
George

George, Say a K&N was doing a good job of filtering sticks and stones, but a horrible job on the smaller stuff...would a OA show this, or would the stock oil filter prevent a reading of say..and oak branch....and a cardinal.


You got me worried, Ive never gotten into the double digit silicon numbers....but is my AFE/K&N..letting in stuff so big it cant be analyized bc my pf2232 is doing good.... Im lost if AFE/KN does good on big stuff, then what micron rating is my OA showing a 7 ppm for.....Im probably not making sense. If it makes sense to you reply, If not ill PM ya


Bill

I switched from the K&N to the UNI when I noticed a light even film of dust in the intake. Up untill then I had always been a K&N fan. I haven't accumulated enough miles on the UNI to check it yet but will soon. I would think the thickness and maze type flow dirt has to take through the oiled foam type would provide superior filtration. JMHO Edited by: a bear

Wouldn't an AFE or K&N with a sock on it work just as well as the foam..? I thought Foam was for real high dust areas like the desert etc? I have the AFE Stage II but if it's not filtering well enough it's going to have to come off..

A photograph of the Uni, please..... A picture is worth a thousands words, as they say....
George





http://www.dieselplace.com/forum/uploads/AA5_Uni_backing_screen.jpg

Hmmmm, that 2 peice filter looks familiar. http://www.dieselplace.com/forum/smileys/Ermm.gif http://www.dieselplace.com/forum/smileys/Shocked.gif

The UNI looks to me to be the same as the old sytle Amsoil filter for the 95 and old 6.5TD (TS-83)http://www.dieselplace.com/forum/smileys/Question.gif

Greg