SES Light - Possible MAF - Suggestions?

Quick story - looking for possible ideas from the knowledgeable members of E46Fanatics:

Finished re-oiling my K&N filter (GruppeM) - about two weeks later my SES light comes on and the car is idling a bit rough as though it might stall (RPS around 1/2k with a mild stutter/jolt). The people at the local auto parts store run the standard OBD-II test (this is the tool, right?) and it comes back with a barrage of codes from fuel-related to cylinders misfiring - nothing really conclusive. A guy in the store that happens to work in a shop tells me its the MAF sensor. Quick Google search tells me to pick up the cleaner and clean the MAF which I did a few days ago. However, the light is still on a few days later and now I'm getting a mild whistle, but almost resembles transmission-ish noises (maybe - I'm not totally sure) at low RPM (1-3k maybe) during acceleration, but only for the first few minutes of driving until the car gets warmed up. Also, occasionally another light turns on at start-up as well for a few minutes and goes off shortly after - see below. I'm inclined to think the MAF just needs replaced and I over-oiled too much for the MAF to be salvaged. I way over-oiled the filter. When I first bought the car a year ago and had the thermostat replaced at the stealership, they advised me that intake boot needed replaced - I'm thinking this might be part of it as well. However, before I start delving into all sorts of work, I'm hoping for some ideas/input. I'm a novice at best and seek out my car buddies for help on everything - I'm not one to tackle stuff on my own - I live downtown and park in a large underground garage.

Thanks in advance - I browse this forum often and it has been a constant source of awesome knowledge.

If you spend $x00 on a new MAF, how do you know it won't get instantly ruined?

Ditch that oil filter, they went out with the filofax and and the carburettor.

If you really must have the extra 2 BHP you think it gives, then change the paper filter every 1000 miles and run on premium petrol.

You'll save hundreds in new MAFs.

Arty - thank you for your suggestions. The filter was something that came with the GruppeM intake that was already installed on the car when I bought it. If there was a disposable alternative, it is certainly something I would look into.

If others have suggestions regarding the other symptoms posted above, input would be greatly appreciated!

Change the intake boot, it's what; $10?

Next get a copy of INPA and a VAGCOM lead and a 16-20 pin adaptor on order from China. Google BMW INPA success for an install guide.

Next use a multimeter to measure the resistance of the two black wires that are the heater coils on the O2 sensors; if you can get to them. Expect 10-20Ohms. Open circuit is a fail.

Clean the MAF if you feel it gives you less errors, perhaps take an airline to the filter to blow out some oil.

Those are your cheap things.

Ha fair enough - I'll get the intake boot replaced. Does everyone think the combination of replacing the intake boot and MAF sensor will fix the problems?

I think your new MAF will get damaged in the same way as the old MAF unless you do something about the filter. It's not a cheap part either to continue replacing it monthly.

Cleaning your MAF is a cheap way to try and fix the issue. Mine resolved a lot of my SES phantom issues. There are a lot of DIYs on the site, takes about 30 minutes.

I made a video when I did mine - http://www.foxandhammer.com/2011/08/...ensor-bmw-e46/

Originally Posted by tfoxsf

Cleaning your MAF is a cheap way to try and fix the issue. Mine resolved a lot of my SES phantom issues. There are a lot of DIYs on the site, takes about 30 minutes.

I made a video when I did mine - http://www.foxandhammer.com/2011/08/...ensor-bmw-e46/

yes try cleaning it before you go out and buy a new one. also if you really have to buy a new MAF search for hyundai MAF on the forums.. You will save hundreds for the same part made by SIEMENS for both e46 and sonata

check this out
http://www.e46fanatics.com/forum/sho...d.php?t=783659

Wow thank you so much for the help - it has been great. Unfortunately I have a 330ci, so I do not think the Hyundai MAF will work. Thoughts on this one: MAF Sensor - Advance Auto Parts

Also, does anyone know what the light is in the picture I posted above? It is next to the SES light and comes on for a few seconds when starting the car and stays on for a minute or two.

If the remanufactured MAF sensor in the link above is a good route, I'll pick that up and replace it this weekend with the intake boot I ordered off Pelican last night. Hopefully those two being replaced will fix my problem. Any other thoughts/suggestions?

Originally Posted by kackles

Wow thank you so much for the help - it has been great. Unfortunately I have a 330ci, so I do not think the Hyundai MAF will work. Thoughts on this one: MAF Sensor - Advance Auto Parts

Also, does anyone know what the light is in the picture I posted above? It is next to the SES light and comes on for a few seconds when starting the car and stays on for a minute or two.

If the remanufactured MAF sensor in the link above is a good route, I'll pick that up and replace it this weekend with the intake boot I ordered off Pelican last night. Hopefully those two being replaced will fix my problem. Any other thoughts/suggestions?

The radiator icon??? The manual should have a list of icons and their meanings... Should be able to find the icons and their meanings online as well. Usually means the fluid is low - check the level every now and then manually. Most of those lights come on when starting the car then go off.

http://www.linquist.net/motorsports/bmw/3manuals/

Nothing better than a video to help diagnose, eh?




Thoughts? The whistling seems to quiet as the car continues to run. The intake boot needs replaced regardless, but I'm wondering if something else is going on if the radiator icon is turning on as well (see picture in first post).

Shameless bump - any thoughts on the two videos posted above?

Had the exact same problem after re-oiling my intake filter. Bothered the sh-t out of me for months. Tried MAF cleaning several times. Finally got a new filter for my intake and borrowed someones MAF, cleared my codes and VOILA, no more SES light. Ended up buying a new MAF and never oiling my filter again.

Bake - thanks for the reply - it is definitely a very annoying problem! When I care, I'd be curious to know the benefits of oiling the filter. Is washing not enough? I'm off-topic here..

Did your radiator light ever come on while you had the same problem? I posted a picture in the first post.

Originally Posted by kackles

Bake - thanks for the reply - it is definitely a very annoying problem! When I care, I'd be curious to know the benefits of oiling the filter. Is washing not enough? I'm off-topic here..

Did your radiator light ever come on while you had the same problem? I posted a picture in the first post.

Nah, think you have a separate issue there.

I'm thinking this should probably be moved to the general forum. I'm thinking I posted this in a "resource" forum.

Any ideas based on the noise heard in the videos? I'm hoping it is just the intake boot, but the fact that the noise goes away after the engine is warmed up and that the radiator light is occasionally coming on makes me think it could be something else as well.

Can a mod move this to the general forum? Car sounds terrible right now - see videos above. Input appreciated!

Good info!! I'm having a SES lights issue (again). I had the SES issue diagnosed by both BMW dealer and an indepedent auto shop and they can't find anything so they just reset the SES light and it went away for a little while and came back on. After reading this, I believe it is just the MAF sensor was dirty and need to clean up. I had a GruppeM air intake installed before and probably due to the oil on the K&N filter had contaminated the MAF sensor causing the SES lights to turn on. I brought it to an independent auto shop to have it diagnosed and he can't find any error so he just reset it but he told me that I need to get rid off the gruppeM air intake and put the OEM air box backed on. He didn't elaborate more on why I need to do this but anyway I did install the OEM air box back on but after a week later the SES light turned back on. This time I went to the BMW dealer to get it diagnosed and same result, can't find anything wrong so they just reset the SES light again. After 4 days on the road, the SES lights turned back on. I told myself, I need to go back to E46 forum (on which I haven't been on the forum for a long long time), to research my issue and walla!! I knew it that my E46 brothers will able to give great information. Thanks E46 forum!! you guys are great!!!

Just wanted to update this in effort to help future searches. I think the I take was part of the problem, but after having persistent problems, and eventually the car losing acceleration power, I had it towed to a shop to have the oil separator replaced. I guess that, along with a few hoses, needed replaced. $900 later, I had enough and sold the car. Before selling, the engine light was back on.

What I learned: Don't buy a BMW unless you're ready for costly repairs. Sorry, these cars just aren't reliable and more sensitive than any car I've seen. Weird things break on them and the bills rack up fast - not sure they're with it. Best of luck to others. My advice - if you owe less on the car than its worth (like I did), get out while you're ahead!