2009 BMW 750i: Check Engine Light

lowmiledude, others can correct me, but I believe most vehicles will clear such codes after a certain number of starts and/or running time. If left alone, this car probably would have cleared the code too.

Why doesn't such an expensive car have a separate "check gas cap" light, like many others?

And why won't iDrive actually tell you what's wrong?

Although I don't blame the car for not shutting off the light after you fixed the gas cap. It takes a few key cycles and evap system checks before that happens; driving 10-15 miles doesn't cut it.

"shouldn't this computer be able to clear the code on it's own once the problem is resolved? Don't virtually all cars do this (or at least you can flash the ECU and it goes away)?"

Don't think so. You can clear it yourself if you have a OBDII reader though. Same with all other cars.

Well, the thing is if you spend that much money on a car like that, you are probably more likely than average to be willing to bring it in and pay for every little thing. Even if they do everything right and treat you nice, dealers still want to see as much of you as possible.

I guess if you have such an expensive car, the downtime is nothing to worry about. because you have other cars to drive.

Since I can't afford a 7 series, I would be aghast at the niggling things that hapen to these cars. Whereas, if I owned a Subaru (which I do), I would be more accepting of it-- after all, I only spent 24K for my 2005 Outback.

I think the bigger problem is the cheap way that BMW tells you that you have an engine problem.

Most cars I know won't clear a code related to the gas cap after that's been fixed. It has to be cleared manually. I'm sure that's a bone they throw to make the dealers happy.

Seriously, I wonder if there is an incentive for automakers to dumb down cars and have the default be a visit to the dealer. The dealers invest a lot of money learning how to repair the new technologies and they make a good living from service charges. In this case, however, BMW had to pay for an unecessary service, but they get the data on early problems that need correction.

Guys,

An important note to remember is that a check engine light will not pass an emissions test, and there are lots of check engine lights that TAKE TIME to come on.

Meaning: If an owner has a problem with an emissions system that takes, say, 100 miles to appear...they could potentially clear the code somehow and get their emissions test passed.

I agree that BMW's system should be able to provide some basic information to the driver. I wonder if it does, but the owners in this case couldn't find it. I ask because even my $20k 2006 Honda Civic SI flashes "loose gas cap" when this happens.

But for clearing it....yeah, automotive makers aren't giving the controls of that to owners in an easy-peasy way just yet.

Joe

P.s. My 1995 volvo 850 turbo had a nice station under the hood where you could connect certain ports and pull codes (via a blinking light display) or reset codes. I do appreciate it when automakers do stuff like that, which gives DIYers a cheap way to manage their auto.

I just had a similar problem with my S-10 and coincidently my '04 Impala. The Impala definitely threw the "gas cap" code as I pulled over, shut the car off, re-did the cap and a few mile later the light went off.

My S-10 however I don't know if it was a gas cap or not. It has only thrown a check engine light a couple of times in it's life - once was a gas cap and I had to replace the cap the other was a loose spark plug wire. So when I threw the code just the other day I tried the gas cap trick. No go. After over 100 miles and a couple shut-offs it was still there. So I undid the battery and let it sit for several hours. Upon plugging it back in, the code was cleared. There is now almost 100 miles on the "cleared" code so we'll see if it comes back on.

The point I am trying to make however is that it appears that even within automakers the ability to "self-clear" codes is inconsistent (if indeed my truck threw the gas cap code which I am pretty sure it did)... however, I think that a 70K plus vehicle should be able to tell you definitively that you need to re-tighten the gas cap...

You can always borrow a scanner for free at Shucks/O'Reily's or similar auto parts store to scan and clear codes. It's helpful to know what code is being thrown instead of just blindly clearing them.

"I ask because even my $20k 2006 Honda Civic SI flashes "loose gas cap" when this happens."

$20k? LOL, not anymore. More like $12k. More or less. But I know what you meant.
Yes every car should tell you "loose gas cap" when it is something as simple as that.

Though maybe ever car doesn't do it, I've definitely encountered quite a few that will clear the CEL if not the code for a loose gas cap after four or five start cycles with the problem corrected.

I had the gas cap problem once in my Acura and it did not turn on the check engine light instead the information display said "Check Fuel Cap". It also gave additional instructions by sending a message to Acura's simpler version of iDrive by having the Navi lady read instructions on how to handle the problem. Paraphrasing she said that a problem has been detected in the emissions control system that may be caused by a missing or loose gas cap. Check the gas cap to be sure it has been tightened to at least one click. If this is the problem the message will turn off within 3 complete driving cycles. The owner's manual adds that if tightening the gas cap does not solve the problem the Check Fuel Cap message will turn off and the Check Emissions System message will be displayed and the check engine light will turn on.

Scary to think that the owner must rely on a computer to check the oil level and the same computer can't tell if the gas cap is loose even when going into the advanced self diagnostic functions of iDrive.

You could always pull the negative cable off the battery for five minutes to clear it out. My $22K Civic Si even keeps the radio presets.

For the longest time I was getting a tire pressure warning light that wouldn't go away... I adjusted my tire pressure but the light persisted. I called my dealer and they asked me to bring it in. They then 'fixed' it and sent me on my way no charge (under warranty). A couple months later the light showed up and I went through the same song and dance to get it to go away. By the third time I complained that this issue was persistent and they needed to fix the tire pressure monitor system for good this time. Well not until then did they think to inform me that this was normal behavior and all they were doing was resetting the system by holding in a particular button for a few seconds while in a particular screen.

Something is inherently wrong with BMW when they think it's a good idea to have a customer make a trip to the dealer for something as simple as a tire pressure warning light reset. I mean first of all I'd like to think the light would go away on its own once the tire pressure was corrected. But if not that, then at least when a customer calls in, see if they're capable of resetting it on their own before asking them to make a trip in to do it for them.

Aside from the inconvenience this caused for me making unnecessary trips to the dealer, it also kept me from knowing if I had a flat tire. Since my car had run flat tires I couldn't just look and tell, so seeing that warning light stay on in front of me while on a road trip kept me paranoid about possibly having a flat and not even realizing it.

That aside my 335i was a total POS and I'll never consider owning one, but this story reminded me of just one of many complaints I had about that car.

Resetting BMW's t.p.m.s on I-Drive is pretty staight forward. I always do after topping up tire pressure and after a flat repair.What is annoying that, unlike most other systems on premium vehicles,the display does not offer the individual tire pressure only only a green (or yellow )light for each tire.

The emission-related (OBD) fault code usually requires certain number drive cycles to confirm a fault code (light up the fault lamp), and it also requires the same number of drive cycles to clear a fault. Adjusting the fuel cap probably cleared the fault condition, but fault code still stayed ON because the required number of drive cycles was not completed. The technician usually use the service tool and issue a reset to clear the fault code, so the vehicle does not need to go through the required drive cycles.

"Don't think so. You can clear it yourself if you have a OBDII reader though. Same with all other cars. "

I can see it now, some rich ahole clearing the code with an OBDII reader on a 6 figure 7 series. I find it funny how you would even have this problem on a 6 figure car that is 1 year old.

"Something is inherently wrong with BMW when they think it's a good idea to have a customer make a trip to the dealer for something as simple as a tire pressure warning light reset. I mean first of all I'd like to think the light would go away on its own once the tire pressure was corrected."

You don't and shouldn't have to go to the dealer to reset the TPMS warning. It's very simple to do in iDrive or slightly more difficult through the OBC if you don't have iDrive. As for the light extinguishing itself when you air up the tires, it doesn't work that way on ANY TPMS system. You always have to reset it yourself, this is done to tell the system what your baseline tire pressure is. What if you chose to deviate from the specified pressures? If it's set to 40 psi but you chose to do 32 the light would never clear.

Stuff like this is why you should read the owner's manual when you buy a car, BMW or not.

I left a BMW dealer after learning horror stories from a few dealer employees. I am glad i didn't purchase a BMW.

I am so tired of people complaining that a 100k car should know to turn off the light when the problem is fixed. Do any of you now why is does not automatically do it? The reason is most drivers are not you and I and are MORONS who know nothing about cars. I sell BMWs and can vouch for this. BMW has you come in so they can check the car over and make the customer feel better about it. They are forced to have 1000000000 dummy lights that come on way too easy because of all the LAWYERS in the US who sue them for anything even though almost all the time its user error and sheer stupidity. We cant just blame the lawyers either we have to blame the judges/jury who find BMW or any other company at fault in the stupid lawsuits. If they made people take responsibilty instead of having major corporations pay millions is lawsuits then people would stop suing all the time.

One more thing about spending 100k on a car. Why does everyone think a car should be reliable if you spend more on it? If you buy a basic tv for $300 it is 100000 times more reliable than a TV that was $10,000. When something cost mroe it contains more things that can go wrong and new technologies that have never been field tested. Why when its a car is it a problem but for anything else high end its OK? When you spend more on most products they become more complex and less reliable. Why is a car different?

rex21 what stories did you hear? BMW is BY FAR the most reliable german car besides Porsche. I guess you went with a Japan appliance.

lowmilelude you are being harsh. The six digits pays for luxury and exclusivity, not a neural net computer core with an A.I. from the star ship enterprise.

It's a car just like any other, and if the ODBII trouble codes get tripped, you're going to get a SES light, which means a trip to the service center. Don't expect a holographic butler to appear and clear the code for you.

viper lol on the holographic butler.

bimmerjay

"As for the light extinguishing itself when you air up the tires, it doesn't work that way on ANY TPMS system."

Wrong!!! The low tire pressure warning on my Acura turns off and resets itself after air is added to them. If it realizes the pressure is 25 psi and can turn on the warning light then it is not much to ask for it to realize that if the pressure is 32 psi then air must have been added and tire pressure is no longer low, light off. Having the dealer reset a low tire warning is silly. I'm surprised BMW doesn't make you go to the dealer to reset the low fuel or low washer fluid warnings.

I agree with alpine6speed, my experience with my BMW has been pretty great. I have had a few problems here and their but what car of this level and complexity does not. At least my acceleration is intended and my brakes work when I step on the pedal. (yea thats right I am talking to you Lexus/Toyota). As far as taking my car into the shop now and then as a BMW owner I realize its going to happen, but its a small price to pay for the very large smile I have on my face when I am driving my BMW.

@allthingshonda,

So how do you reset or change the baseline PSI in your Acura? Low tire pressure is relative, it's not an absolute like low fuel or low washer fluid.

"Having the dealer reset a low tire warning is silly."

Did you read what I wrote? You *do NOT have to go to the dealer*. You hit the TPMS reset when you get in the car and it's done. Numerous systems work this way. The button tells the system "I have just set the pressures and this is what I want you to recognize as proper." The system then calibrates its % deviation warnings from those values. threxx clearly didn't take the basic step of reading the owner's manual and chose to drive to the dealer.

@bimmerjay

"You don't and shouldn't have to go to the dealer to reset the TPMS warning. It's very simple to do in iDrive or slightly more difficult through the OBC if you don't have iDrive. As for the light extinguishing itself when you air up the tires, it doesn't work that way on ANY TPMS system. You always have to reset it yourself, this is done to tell the system what your baseline tire pressure is. What if you chose to deviate from the specified pressures? If it's set to 40 psi but you chose to do 32 the light would never clear."

No, I also have a Toyota 4runner and Saturn Aura and both of those cars clear their tire warnings as soon as pressure is back to normal. I haven't checked on the Aura but the 4runner does offer a method of programming a new baseline pressure, too. But don't you think it makes more sense for the light to clear itself automatically rather than requiring the driver to read the manual and go through a non obvious procedure? And then if the owner wants to do something so advanced as to set a new baseline pressure... THEN they can read the owner's manual and follow a more advanced procedure. Typical German engineering though.

"threxx clearly didn't take the basic step of reading the owner's manual and chose to drive to the dealer."
I'm a fairly technically inclined guy. I tried what I perceived as any obvious potential reset methods to no avail... but most importantly I just assumed that a tire pressure monitor system would reset its own light once the condition was corrected.

Aside from that, I didn't choose to drive to the dealer, I chose to call the dealer which didn't bother to tell me this was a DIY type fix... they just asked me to come in. Multiple times, no less, without ever showing me how simple of a fix it was.

@threxx,

I can't make excuses for or explain why the dealer didn't provide you with better service. Unfortunately it happens all too often that they don't explain simple things like a TPMS reset to alleviate a customer hassle.

I also strongly believe that everyone should read their owner's manual upon getting a new car. Especially when you consider that there are different engineering and ergonomics philosophies across the continents - particularly important if you're new to the brand. There's no way every function and feature is going to match your intuition on how it's properly used. Regardless of whether it's Japanese, German, American, or Korean.

Even if I didn't always read my owner's manuals cover-to-cover I would crack it before I called the dealer (who, unfortunately, is often wrong) if something didn't seem to be working correctly. If you have iDrive, going to the 'Tires' screen even gives you instructions on the TPMS reset procedure, which as mentioned involves clicking the big "reset" on the screen when the car is stationary.