EML Problem

So the other day I was driving and first my DSC then EML light came on. I lost all power in 5th, and in all other gears, power was sporadic. It was as if my fuel/air ratio had gone to crap. BUT, I pulled over and restarted the car. EML went away, and the car ran fine. But minutes later, back on the highway, the DSC and EML came back on, killing my power.

I went to Erie's BMW dealership, and they scanned the codes. Here are the relevant ones:

00A9 DME: Engine throttle output stage shutoff after daign error
006F DME: Signal, pedal travel sensor (in thr) pot 2 (OBDII: P1542)
00AC DME: Signal, pedal-travel sensor (in thr) pot 1/2 short circuit (OBDII: P1542)
0075 DME: Plausibility, signal, pedal travel sensor (in thr) pot 1/2 (ODBII: 1542)

I was told I needed a new Throttle Body, and was quoted $800. BUT, I know TB's usually don't go back on E46s. So my plan is to just clean the TB.
I'll also clean my DISA and ICV.
There are no holes in my intake tubes.


Some questions:
What is the EML? Why does the computer kill my performance?
If I drive with the EML light on, can it do damage to the car? (I need to drive in 30 miles to get back to my house)

As always, thanks for the help!

Originally Posted by TiAgTouring

I was told I needed a new Throttle Body, and was quoted $800. BUT, I know TB's usually don't go back on E46s.

True enough except for the 323. Those throttle bodies die CONSTANTLY. My own 323 went through 3 of them. My friend works at a BMW junkyard and they sell TONS of them as well.

A used one is $125-$180, (you can use yellow or blue label, I tried and they both work) you should just do that. Cleaning them CAN bring them back to life, but not forever. Just replace it and move along.

Yes, you can drive in EML mode, but as you know, the second you hit 2000 rpm you have no power. it is hard to drive that way.

ahh okay. Good info on the TB. I know mine is a mechanical TB, but the tech at the dealership still said I had to have it programmed. This confused me. Thoughts? Thanks

Originally Posted by TiAgTouring

ahh okay. Good info on the TB. I know mine is a mechanical TB, but the tech at the dealership still said I had to have it programmed. This confused me. Thoughts? Thanks

I have a 2000 323i, which has the mechanical TB. I am having problems with mine as well. I have done a lot of research, but can't seem to get all the information I need. I do think I can answer your question, however.

Even though our TBs are mechanical, they have sensors built in that tell the computer how "open" the butterfly is. The computer takes this into account when adjusting air/fuel ratio, etc. Apparently, each throttle body is unique in the signal it sends to the computer. The computer learns each new TB, and stores what it learns as "adaptations". Thus, when you install a new TB, you must reset the adaptations as the old ones will not work with the new TB. The computer learns the new TB as you drive, and all should be well.

I understand that there are some diagnostic tools specifically for BMWs that will let you reset the adaptations yourself. I am not expert on these. It might be worth having the dealership or other qualified mechanic reset the adaptations for you. However, beware. When I asked my mechanic to reset them for me, he said he would not do it unless he diagnosed and fixed the problem himself.

Amazingly, I just reset the throttle, and everything has been Okay. I will go ahead and clean to TB and ICV just in case though. Here is what I did:

"Resetting Throttle:

"The Throttle is "Drive By Wire" and adapts to your particular driving
style. Do a TBA Throttle body adaptation.

1. Get in your car, it doesn't matter if you close the door or not.

2. Turn the key to the on (not start) position, the position just before the starter turns over.

3. Press the gas pedal to the floor with the key in the "on" position.

4. Hold the pedal to the floor for five seconds, then turn the key back
to the "off" position (don't remove the key), then release the gas
pedal.

5. Wait 2 mins. for a full alignment.

6. Drive the car as you always do"

Good deal. I guarantee the dealer would have just replaced the TB without every trying the adaptation method first.

For more info on the EML and throttle body on the MS 42 ECM BMWs see pages 51-54 of this document:

http://www.beisansystems.com/misc/SE...CONTROL_SYSTEM.

It sounds like you are in Emergency mode 1 - ignition timing retarded, fuel injection reduced, but still able to reach full speed with limited power.

EMERGENCY OPERATION 1
• Activation of the EML warning lamp.
• MDK is deactivated, the throttle valve is opened mechanically by the springs and throttle
cable.
• To maintain vehicle control, the MDK opening is compensated for by closing the idle
speed actuator and retarding the ignition (engine power reduction).
• Engine power is further limited by fuel injector cutout.
Emergency operation 1 limits the dynamic operation if one or more of the potentiometers
fail. The engine can slowly reach maximum speed with limited power. The EML light will
be illuminated to alert the driver of a fault

^ Yes, exactly. Great info.

So I drove 1000 miles without the light coming back on. But Alas, It has showed up three times over the last two days. I can power the car off, reset the throttle (or disconnect my MAF and lock the car to reset the comp), and the light temporarily goes aways.

Thus the answer is its time to get my hands dirty. I am about to do the following-- most related to EML, but also as part of good maintanence that will only help the situation:

1) Restore stock air filter
2) Clean ICV
3) Clean TB (without uninstalling-- but check seal)
4) Check DISA to ensure working properly, and clean
5) New spark plugs (its been 30-40k miles since my last)

Depending on how those go, I might also get a new fuel filter-- its always a good thing to have new and clean.

Will report back

There was a post today where someone explained the eml light pretty well.

Your plugs should be good for 100K miles if you got the right ones...and if you're returning to stock filter, was your old filtered oiled? If so, clean your maf again when you have things apart.

Also, I don't know that you can check the seal on tb without removing it...it's a $5 gasket or something like that. If tb is off, worthwhile to do that now while you can easily.

Beyong that, I'm not up on eml lights at all!

Wow..I didn't realize the plugs were good for that long. I was about to order some, but am now reconsidering.

Today I cleaned the ICV, DISA, and TB (without uninstalling it because of my custom setup with the M54b30 Manifold)

I fear my DISA is bad-- it wiggles about 1mm, but more importantly, makes a clicking sound like crazy when the engine is going. The sound stops when I unplug the connector. Could the EML light really be due to a bad DISA?

I've also seen P1542 related to fuel issues. My EML/DSC lights first came on when I had 30 miles left in the tank. I'm thinking a fuel filter can't hurt-- my last one was 30k+ ago.

I've got a 150 mile drive back to Athens tomorrow, so hopefully the problem doesn't come back. But I know there is more to do...

So the EML problem went away for 800 miles...but has returned now.

I installed a new German Auto Solutions DISA flap, but that did not solve the problem.

I've done everything except get a new TB--so its that time. Does anyone know if I install a new TB, can the car be driven before it the TB must be electronically adapted to the car's ECU? This makes a huge difference, because if so I will have to leave my car in Cinci where there is a dealership.

Originally Posted by TiAgTouring

So the EML problem went away for 800 miles...but has returned now.

I installed a new German Auto Solutions DISA flap, but that did not solve the problem.

I've done everything except get a new TB--so its that time. Does anyone know if I install a new TB, can the car be driven before it the TB must be electronically adapted to the car's ECU? This makes a huge difference, because if so I will have to leave my car in Cinci where there is a dealership.

You spent a lot of money and time you could have saved if you had heeded my post. No, they do not have to be coded. All you do is plug in the new one and go. And FYI, they made a blue and yellow label, they are interchangeable so don't let that fool you or let anyone tell you otherwise. I have done it, THREE times. Yellow is harder to find and better IMO.

Originally Posted by TiAgTouring

So the EML problem went away for 800 miles...but has returned now.

I installed a new German Auto Solutions DISA flap, but that did not solve the problem.

I've done everything except get a new TB--so its that time. Does anyone know if I install a new TB, can the car be driven before it the TB must be electronically adapted to the car's ECU? This makes a huge difference, because if so I will have to leave my car in Cinci where there is a dealership.

I may not be as experienced as others, but my own experience indicates that the new TB should be adapted before driving. If you don't, your car may be limited in speed to such an extent that a drive home would be worse than the effort required to adapt. Of course, the two TB's I have installed were both defective, which only added to my problems. However, everything I have read suggests that this is a necessary step. I have some info that may be relevant. I will try to find and post it.

Originally Posted by shanneba

For more info on the EML and throttle body on the MS 42 ECM BMWs see pages 51-54 of this document:

http://www.beisansystems.com/misc/SE...CONTROL_SYSTEM.

It sounds like you are in Emergency mode 1 - ignition timing retarded, fuel injection reduced, but still able to reach full speed with limited power.

EMERGENCY OPERATION 1
• Activation of the EML warning lamp.
• MDK is deactivated, the throttle valve is opened mechanically by the springs and throttle
cable.
• To maintain vehicle control, the MDK opening is compensated for by closing the idle
speed actuator and retarding the ignition (engine power reduction).
• Engine power is further limited by fuel injector cutout.
Emergency operation 1 limits the dynamic operation if one or more of the potentiometers
fail. The engine can slowly reach maximum speed with limited power. The EML light will
be illuminated to alert the driver of a fault

Turns out the info I was thinking of was already in this post. Read pages 51 to 56. HTH.

Originally Posted by smolck

You spent a lot of money and time you could have saved if you had heeded my post. No, they do not have to be coded. All you do is plug in the new one and go. And FYI, they made a blue and yellow label, they are interchangeable so don't let that fool you or let anyone tell you otherwise. I have done it, THREE times. Yellow is harder to find and better IMO.

So yes you're right, but I needed to do the DISA valve anyway--it was rattling and going bad. I ordered a used TB from your friend--- thanks for the info!

BUT-- When I was driving home, I noticed something interested. The EML light would not come on when I used cruise control. It was as if the throttle body would only have problems when manually controlled (although I realize the cruise control still moves the pedal).

Does this imply my pedal could be bad? Or does it imply nothing?

Originally Posted by TiAgTouring

So yes you're right, but I needed to do the DISA valve anyway--it was rattling and going bad. I ordered a used TB from your friend--- thanks for the info!

BUT-- When I was driving home, I noticed something interested. The EML light would not come on when I used cruise control. It was as if the throttle body would only have problems when manually controlled (although I realize the cruise control still moves the pedal).

Does this imply my pedal could be bad? Or does it imply nothing?

Perhaps the pedal sensor, which is built into the TB is bad. When you replace that all should be okay.

Originally Posted by TiAgTouring

So yes you're right, but I needed to do the DISA valve anyway--it was rattling and going bad. I ordered a used TB from your friend--- thanks for the info!

BUT-- When I was driving home, I noticed something interested. The EML light would not come on when I used cruise control. It was as if the throttle body would only have problems when manually controlled (although I realize the cruise control still moves the pedal).

Does this imply my pedal could be bad? Or does it imply nothing?

Eh, is likely just an anomaly. I wouldn't worry about it. Besides, does a drive by cable car even have a pedal sensor (not the kickdown sensor)? I don't remember if my 323 had one or not, but why would it? A cable tells the butterfly how far to open so it shouldn't need one.

And to repeat, you DO NOT need the new TB reset or coded in any way. It is plug and play. I have done it, many, many, many times.

I had the same problem as you and just got my throttle assembly replaced the other day. Just getting it replaced did nothing but get rid of my EML light it still had no power so I brought it back to the mechanic and they said they had to download some computer codes I'm guessing for the ECU. So after they did that everything was fine I had the power back and it felt like normal. But today I started my car in the morning and after 30 seconds of staying idle it stalled out. Somehow I managed to drive to school and it stalled out at every stop sign and light unless I put it in neutral and revved the engine. But after school I got in my car and couldn't start it without it stalling. So I got it towed to my mechanic and they have it now still no word on what's wrong with it now but just letting you know the throttle assembly probably isn't all that's wrong with it.

Originally Posted by Br3tt71

I had the same problem as you and just got my throttle assembly replaced the other day. Just getting it replaced did nothing but get rid of my EML light it still had no power so I brought it back to the mechanic and they said they had to download some computer codes I'm guessing for the ECU. So after they did that everything was fine I had the power back and it felt like normal. But today I started my car in the morning and after 30 seconds of staying idle it stalled out. Somehow I managed to drive to school and it stalled out at every stop sign and light unless I put it in neutral and revved the engine. But after school I got in my car and couldn't start it without it stalling. So I got it towed to my mechanic and they have it now still no word on what's wrong with it now but just letting you know the throttle assembly probably isn't all that's wrong with it.

Might want to leave advice giving to people who actually work on these cars themselves and have a LOT of experience. You shop fed you a line of BS.

Originally Posted by smolck

Might want to leave advice giving to people who actually work on these cars themselves and have a LOT of experience. You shop fed you a line of BS.

Just telling him what happened to me cause the same problem happened to me this week douche bag