My first Check engine light

[Platanos]

It came on two days ago. Been searching the forums for some answers and read that AutoZone did free readings. Well I just got back from the local Zone. The code is

P1174
Fuel Air Metering

What dies this mean? Is it the mass air flow sensor? I don't even know what that is!

How do I fix it?

Once fixed, will the light go out?

Thanks,

[adempster1]

Have you checked to make sure the gas cap is tight? Mine has come on several times due to the cap being loose. I tighten it reset the computer and problem gone till the next time a New Jersey full service station pump person puts it back loose after a fill at the pump.

[Platanos]

Yeah, I searched and read that the gas cap may cause the light. It's on tight.

[Phil Marx]

Sounds like it could be an oxygen sensor fault but that's just a guess. I believe you have two of them on your car. You may have to take it to people who actually work on BMWs for their interpretation. OBD-II sucks! The government trying to protect you; phooey.

[Platanos]

I was told that Fuel Air Metering is the Mass Air Flow Sensor. I did a search and came up with nothing. Anyone have any information as to how I can fix this? Does the MAF go by any other names?

[mohaughn]

The loose gas cap will turn up a different code...

Doing a google search on that codes turns up a couple of different hits that say it means that car cannot control the fuel/air trim properly.

The recommendations are to make sure that you have no vacuum leaks, check all of the vacuum hoses or possibly replace the O2 sensors if they are the original sensors and you have high mileage. The articles I found also state that some vacuum leaks can be very hard to find if you cannot obviously find a cracked hose. For instance the intake manifold gasket or the fuel injector o-ring could cause a vacuum leak and that would probably be hard to find without just taking things apart. Not sure of your mechanical abilities so this might be a job for an experienced mexchanic if you can't find any obviously cracked vacuum lines.

If you know your car has the original, or very old, O2 sensors you could just throw money at the parts but that may not turn anything up for you.

Did autozone reset the CEL and it came right back on?

[Platanos]

Wow, Thanks, thats alot of info. I didn't try google... This seems pretty intense, I'm afraid I don't know anything about vacuum leaks... Autozone did not reset the light... I didn't know they could. The o2 sensors have never been changed (70k miles)...

If I keep driving like this will it cause a problem?

[CirrusSR22]

BMW Specific Codes

http://www.obd-codes.com/trouble_codes/bmw/index.php

They list it as.... "P1174 Fuel Trim Adaptation Additve Bank 1 Malfunction"

Here's some other BMW related posts:

http://forums.bimmerforums.com/forum/showthread.php?t=516261&highlight=P1174
http://www.bimmerfest.com/forums/showthread.php?t=43428
http://forums.bimmerforums.com/forum/showpost.php?p=2644195&postcount=7

Unfortunately there's no definitive answer.

[mohaughn]

Platanos- I'd reset the computer and see if the fault light comes back. One of the articles that I read earlier said the first thing to make sure of is that it is not a glitch. So if you reset it and it never comes back, don't worry about it. If you reset it and it comes right back I'd take it to a mechanic.

I replaced the O2 sensor on my Ti well after 76k miles, but it had a lot of higway driving. If you don't drive the car on the highway very much or do a lot of short trips where the car cannot get up to normal operating temperature deposits build up on the O2 sensor and it will eventually not be able to work properly. Sometimes you can just go and run the car up on the highway for 30+ minutes and it clears the crap off of the O2 sensor.

Can it hurt the car? Yeah, it could. I think some folks on here have said that running really lean can cause some serious issues. You will probably also get really bad gas mileage.

Here is some good info on how the O2 sensor works, and when it should be replaced and why it fails.

http://www.autohausaz.com/bmw-auto-parts/bmw-emissions-oxygen-sensors.html

[scabzzzz]

Good luck on stoich related problems. THe biggest hastle ever. Thank you BMW. Get back in the zone and have them clear your code and see if it comes back on. Thats step one. Another cool trick is to take it to a mechanic and have him run it through a smog machine/smoke machine. It will put smoke through all of your evap lines and if there are any leaks then it will leak out of the cracks or gaps in your vacuum lines. Cool machine. Shouldnt cost you much either. You could probably fix it yourself if you can eliminate the places where its NOT coming from. Its all trial and error bro.