BMW M5 Forum and M6 Forums banner

Filter - MAF poll

  • I've used K&N with no problems.

    Votes: 7 21.2%
  • I've used K&N and they fouled the MAF's.

    Votes: 9 27.3%
  • I've used BMC with no problems.

    Votes: 1 3.0%
  • I've used BMC and they fouled the MAF's.

    Votes: 1 3.0%
  • I've used another brand of filter with no problems.

    Votes: 2 6.1%
  • I've used another brand of filter which fouled the MAF's (please post details)

    Votes: 0 0.0%
  • I have stayed stock, and no MAF issues.

    Votes: 7 21.2%
  • I have stayed stock, but still had MAF problems.

    Votes: 6 18.2%

  • Total voters
    33
1 - 9 of 9 Posts

·
Banned
Joined
·
236 Posts
Discussion Starter #1
I am interested in finding out the extent of problems S62 owners have had with various air filter upgrades.

I did a search here, and it looks as if the two principle oil based filters out there have caused a lot of problems with the MAF's.

With this poll I'd like to try to get an overview on what works and what doesn't.
 

·
Registered
Joined
·
2,679 Posts
Installed K&N and fouled MAFS.

To be fair to K&N, I took the filters brand-new, out of the box from their cellophane wrapping, and installed them on the day before a track weekend at Road Atlanta. By the third session (with plenty of WOT :blink: ), I encountered hesitation and stalling problems that continued intermittently.

Thanks to this board, I found out that at least a half-dozen others had been down the road before me, and I took printouts that HadE55NowM5 had posted into my Service Advisor. He read them and agreed with the diagnosis, but said his hands were tied by what the OBD-II would tell him. Which was 'cat fault,' so I got two new cats that I didn't need.

I had to go to another dealer to get them to change out the MAFS.

After all this headache, I decided that the cost-benefit ratio was too heavily weighted on the cost side. I put it back to stock, and gave the K&Ns to my big brother. Incidentally, he runs them in his E39 540i/6 and has NEVER had any related performance problems. Go figure.

-Dave
 

·
Registered
Joined
·
330 Posts
This response pertains to those ONLY modding their intake on E39 M5, so let not get it twisted.

I would keep your intake system stock. :nono: Why:

1. there are no noticeable gains and you probably lose horsepower.
2 The intakes that do have gains are like 1-5 HP and at high RPMs in which driving around town daily, well im sure most of us are not redlining. You are most likely losing HP at regular driving especially if you live in hotter areas or climates. I dont think any drop in filters have shown any real gains besides psychological.
3. The cost of the intake systems on the market is NOT a value considering the very minimal if any performance gains you are getting. Some drop in filters are also ridiculously expensive.
4. MAF's are delicate and prone to failure. You are just increasing your chances of premature failure.

I had the GruppeM intake and you could feel the loss of power due to heat soak. (Im in SO. Calif.), within weeks i had MAF failure and check SES light. I cannot totally blame it on the intake system as the car was purchased used and it had 60K miles when GruppeM installed, however i feel it had some relation to them failing.
 

·
Registered
Joined
·
1,045 Posts
With aftermarket filters your MAFS will go bad Faster then with stock, as aftermarket filters tend to let some to get trew...and they will go bad even faster with CAI....

That is the only reason why I didnt get aftermarket air filters when I've got new MAFS...
 

·
Registered
Joined
·
5,226 Posts
I have 40,000 miles on my MY01 and 34,000 miles have been with the AA CAI and H&K filters. Not a single MAF issue in all that time. Do the filters affect the life of the MAF's, I do not believe it and someone would need to explain the theory behind that statement.

I have lived and driven my car in temperatures up to 110 degrees in California and here in Houston humidity levels at 100%. The AA CAI was not an expensive upgrade and while no proof on a dyno can be seen, you can feel it with the car. That being said, this mod. along with a Powerchip upgrade and perhaps a Tubi exhaust as well as headers would all combine for improved horsepower and drivability.

Sometimes dyno runs are only half the story.

Mark
 

·
Banned
Joined
·
236 Posts
Discussion Starter #6
Mark, the issue as I understand it is that filter elements that use oil on fabric have a tendancy to let go of some microscopic particles of the oil into the intake system. If these paricles settle on to the MAF sensor they can build up a film which will drastically alter the engine management system's functioning. The most common thing that I have heard of is a loss of power above 4,000rpm, with the car eventually feeling as if it is in limp home mode.

Some say you can clean your MAF's, and some have tried without success, most have needed the EMS reset in some way, as there is an error code issued by the EMS which gives you an SES light, and logs the error in the car's memory.

As you know we Z8'ers share the same S62, and I am trying to build up the best possible overview of this issue as it relates to after market products, so we can all learn from the combined experience of a large number of S62'ers.




MAH said:
I have 40,000 miles on my MY01 and 34,000 miles have been with the AA CAI and H&K filters. Not a single MAF issue in all that time. Do the filters affect the life of the MAF's, I do not believe it and someone would need to explain the theory behind that statement.

I have lived and driven my car in temperatures up to 110 degrees in California and here in Houston humidity levels at 100%. The AA CAI was not an expensive upgrade and while no proof on a dyno can be seen, you can feel it with the car. That being said, this mod. along with a Powerchip upgrade and perhaps a Tubi exhaust as well as headers would all combine for improved horsepower and drivability.

Sometimes dyno runs are only half the story.

Mark
 

·
Registered
Joined
·
330 Posts
I think if you look at all the people w/ intake related problems, basically you are just gambling that your car will run ok or you willl have some kind of MAF failure and problems. No 2 cars are the same and i think there is too high % of people having some kind of problem be it MAF premature failure, SES lights, car bucking and boggin or going into limp mode, and / or a combination of all the above.

Too much risk for 2 HP gain if that.
 

·
Registered
Joined
·
5,226 Posts
macfly said:
Mark, the issue as I understand it is that filter elements that use oil on fabric have a tendancy to let go of some microscopic particles of the oil into the intake system. If these paricles settle on to the MAF sensor they can build up a film which will drastically alter the engine management system's functioning. The most common thing that I have heard of is a loss of power above 4,000rpm, with the car eventually feeling as if it is in limp home mode.

Some say you can clean your MAF's, and some have tried without success, most have needed the EMS reset in some way, as there is an error code issued by the EMS which gives you an SES light, and logs the error in the car's memory.

As you know we Z8'ers share the same S62, and I am trying to build up the best possible overview of this issue as it relates to after market products, so we can all learn from the combined experience of a large number of S62'ers.
I agree with you about the coating being released from the fiters. It appears that it is not a consistent problem from all users of K&N. I have also heard of the MAF's being cleaned with success using electronic cleaner.

I wonder if cleaning the MAF's with this appropriate cleaner helps for all our cars? Certainly a film must build up over time like it does on the inside of your car on the windows. It would appear to make sense to attempt to clean the MAF's even if you are running with the OEM filters if this is the case.

What do you think?

Mark
 

·
Banned
Joined
·
236 Posts
Discussion Starter #9
It would certainly make sense that a film, like the one that builds up on the windows, must appear regardless of filter over time, so it makes sense that cleaning MAF's should be a good idea. The only downside I can see is they seem to be fragile, tempramental and don't always respond well to cleaning, based on the various MAF posts I've read.



MAH said:
I agree with you about the coating being released from the fiters. It appears that it is not a consistent problem from all users of K&N. I have also heard of the MAF's being cleaned with success using electronic cleaner.

I wonder if cleaning the MAF's with this appropriate cleaner helps for all our cars? Certainly a film must build up over time like it does on the inside of your car on the windows. It would appear to make sense to attempt to clean the MAF's even if you are running with the OEM filters if this is the case.

What do you think?

Mark
 
1 - 9 of 9 Posts
Top