Project E46 M3: Part 8 – The dreaded EML Light



The fusebox in an E46 3-Series is inside the glove box, and it drops when unlocking the two white tabs.  Removing this #29 fuse with the key in the “off” position, and reinserting, was the quickest way to reset the EML light so I wouldn’t have to call a tow truck (pulling the #1 TPS plug would do the same thing in the engine compartment).

Thankfully, we made it to St. Louis, although not without performing a dozen or so fuse-resets, but we got it down good enough to be able to do it on the fly (in the slow lane).  It wasn’t until later in the weekend, while lying in the hotel bed thinking about it, that I realized this had to be a voltage issue.  After all, the problem always seemed to happen while cruising.

So, on the entire way home, I gave the car a rev blip, or dropped it down a couple of gears and accelerated to 5000 rpm.  In the entire 4-hour trip home, and then some several months later, I never had a hiccup again as long as I did this.  In my mind, the VAC alternator underdrive pulley would eventually have to go, although I also realized I could keep doing this and keep the extra few wheel ponies I got from my pulley install in Part 2!  For the time being, I had chosen the latter and kept the pulley.

A few months later, in the spring of 2014, the battery light came on, and stayed on, but the symptoms never changed.   Fast-forward to August, 2014, however, and the EML light came back after a third-to-fourth-gear rip, right as I got into fourth, and stalled the car.  Well, this was new because the EML light had never happened at wide-open throttle.  It was a tell-tale sign that things were getting worse.  Thankfully, a quick #29 fuse pull once again allowed me to make it home.   But in my mind that pulley now had to come off.


We knew the alternator itself wasn’t an issue because we’d recently installed a remanufactured factory Bosch unit from Bavarian Autosport, we just hadn’t featured it yet.  At idle, however, with the large VAC alternator pulley on there, voltage would be around 12.55 volts, whereas we wanted to see at least 13.5 volts.  We suspected that a possible low voltage was reaching the ECU, and triggering the EML light.  To confirm, we were set on swapping the alternator the pulley back to stock.


Even with open access to the alternator, which for us required removing the top coolant hose so we could remove the plastic radiator shielding, that pulley was on too tight for our air tools.  So with a good grip on some large pliers we were able to get it loosened up with one set of hands.  The pulley pictured here is actually the stock one going back on.  Note the size difference.

While VAC didn’t have a new belt available to switch to a stock pulley (because we were keeping the two pulleys underdriving the water pump and power steering), Gates came through with its K060605 Micro-V accessory belt, which fits perfectly.  If you want a belt that will last, Gates is pretty much the name for automotive belts.  They even supply belts for NHRA’s Top Fuel 10,000hp dragsters, which you can see HERE!

Unfortunately, after firing the car back up, there was no difference, except for now the EML light would only come up after wide-open throttle, and NOT while cruising!  So the symptoms had flipped!  To add salt to the wound, the battery light wasn't going away either.  What on earth was going on here!!!  The only change between pulley swaps was an engine wash while everything was out, and because some coolant had gotten spilled.  Could we have faulted TPS #1 now by getting it wet?  We’ll share that later.

The drive-by-wire sensors include the #1 TPS above the oil-filter housing, the one in the accelerator pedal, and the one underneath the intake manifold, on the throttle actuator.  A new TPS sensor runs a little over $100, and a new pedal with sensor included runs about $140.  The throttle actuator itself retails for over $600, so we were hoping it at least wasn’t that!


  1. i have an EML issue in my bmw 323i e46, model 2002 and ive change the entire engine and it wont just go off, what do i do ? amimiservices is me mail, please can anyone help

  2. I just wanted to say, “Thank you.” My 2000 328ci went into “limp mode w/EML light on” while driving home, the other day. I was able to get off the freeway, and safely park. While I was wondering what the heck was happening, I started searching for solutions, and that is how I found y’all’s website.

    Although I don’t have an M5, I was able to pop the fuses, that got my vehicle acting normal, and I was able to get home. That piece of information was priceless.

    Now, I am chasing down what caused the issue. So, last night a buddy and I removed and cleaned the mass airflow sensor, idle control valve, and throttle body. Unfortunately, I thought there might have been a throttle position sensor somewhere within all that removal process, but there wasn’t. I also thought that there may have been one attached to the throttle body, and there wasn’t.

    To keep a long story short, I put everything back together, cleared all my fail codes, and all seems, “so fas, so weird.” All in all, thank you for taking the time to document your fails and victories, so other may benefit. Rock on!

    1. Hi, so what did fix the eml light? Mine just tirned on the other day. I was letting yhe car warm up. Suddenly the car died and when i restarted it, the eml light was on and seem to be misfiring.

  3. What a great article. I have a 2000 E46 328Ci doing exactly the same thing. I will take this article to my mechanic at Bavarian Motor Tune Services (BMTS) in Brisbane, Queensland, Australia, and ask him to emulate your course of action to possibly rectify this dreaded fault. Cheers mate.

  4. Hi i have a e46 320i 1999 model and have the same eml and traction control light at the same time on and then it will go in limp mode.its been going on sins last wheek but in the 1st day or so i only switch the car of and start it again and the light will go away for 3 or 4 days but now im stuck in limp mode and swithing it of doesent seems to work no more.can any one pls help?????????

  5. Hello, i truly need help. My brother has a bmw e46 (1999) and the eml comes on after a while and goes into limp mode. He changed the air massfillter but the mechanic was unable to erase the error code. He is now pulling the fuse 29 but what else can he do. He really needs his car for work… Any advise would be appreciated.

  6. hi. would start with changing out the TPMS sensors. cheap and easy to get to. Current owner of this lroject car had it happen again and it cleared it right up. Hope this helps.

  7. Hi, I have a BMW e46 ( 2000) and am having EML issues. It first started with fuel not returning from d second tank and I changed the fuel pump and the return verve and it was perfect for like an hour but discovered the the car started misfiring again the moment the eml light came up again. Please, I need urgent help!

    1. Other than making sure you read the entire article, you’re unfortunately in a position to start diagnosing. Much like Pablo’s process, it’s just a matter of going down the list of related components and eliminating them one at a time. Sorry we don’t have an easy answer for you.

  8. I’ve got an 05 M3 zcp 6spd and I’ve replaced the TPS #1 with a new BMW sensor, I’ve got a new throttle actuator (BMW), and swapped multiple pedal assemblies, changed the MAF, cleaned the throttle bodies, and even changed the DME !! I still have an EML light and get TPS codes. All the fuses are perfect and the car has a new battery and new alternator and new belts, pulleys, and idlers (all BMW) I have a genuine EML nightmare. The car used to randomly buck on throttle once in a blue moon until it got more and more prevalent. This has been going on for well over a year now.

    Any input would be much appreciated. Maybe I missed something ? Something to recheck ? Thanks.

  9. Wow glad all bmw owners share in this subject. Only hav had Suv 3 fir 6 months. Just got out of shop w electrical issues $2400 later few weeks after driving back from lake two hours on road for car bog down like I shifted into lie then was fine. 10 minutes later did it again but then the EML light and ck engine light flashed on then off.
    Fifteen min later happened again and thought car was going to stall. Pulled off road read up on what might b going on. Drive at 60 mph and it didn’t happen fir rest of hour trip. Went arrived at home attached diagnostics plug in. Showed no error code.
    Had son who is master certification auto mechanic ck car out to no avail. Car ran fine during trial drive. Going ck and replace censor. Luv car but this seems to B major issue with BMW a.

  10. thanks guys for sharing good info had also my eml light on will most defnat trying out all shared info keep doing well guys u rock

    1. Ainut mikä on hyvä systeemi ja vika poistuu on ,viedä auto paaliin.👍meillä on ollu e46 325i -99 ja ei ole ollut muuta kun vikaa.

  11. Hi, I have a BMW e46 ( 2000) and am having EML issues. I am experiencing rough idling cylinder 2 n 6 misfiring.I changed petrol pump,plugs,petrol filter and all vacuum pipes and ensuring no air leaks.Please, I need urgent help!

    1. Regarding spark issues, I am assuming you changed out coil packs too, as this can be an issue with lots of cars, not just BMWs. You can start by swapping them and seeing if the spark issue is still with #’s 2 and 6. And, if it’s like with E36, there is a plug for all six wires going to the coil packs (so make sure that is screwed on tight–happened to me once with my E36). Regarding EML, I can’t think of anything else other than replacing what we discussed in article and above in the comments already: TPMS sensor at the front of the motor, throttle actuator (should be under your intake manifold like with this car, I’d imagine) and then the TPMS sensor at the throttle pedal, but the whole pedal assembly itself is pretty inexpensive. Good luck

      1. I have replaced the mass air flow sensor with a brand new pieberg one and the dreaded EML light not going off.Put the car on the computer and the error code P 1509 ,P 1550,P0505 Idle Speed Control valve opening coil and closing code.I have dealt with the air leaks and the circuits are still original but still the EML light on.What else can i look at

        1. Yeah sorry but not sure here. All of my EML issues with throttle related, hence the parts I had to replace to make it go away. In your case sounds like a simple idle control valve replacement if you haven’t already. It’s like $100-200.

          1. Worst case scenario I would consider would be a leak around the gasket of the heater core , if it would be like the heart of the problem. I’m dealing with a similar issue kind of : The details ☆ basically I had to evacuate my 325 ci with knowing of its almost completion as far the mechanical issues, the registration at the time of purchase I had to lift the lein sale from a prior owner.
            Thus far I swopped the water pump to Stewart so the Circulation PSI should be up like 20% new hoses new aftermarket pulley new radiator expansion tank both belts serpentine and accessory coolant sensor valve and ECT, NEW oil with Mann filter. Both thermostats Initially the problem during purchase was a over heating issue not constantly but after being driven with a misfire on only cylinder four which pointed to ignition coils on the OBD and lein fuel in both lanes 1&2., what I decided to do to avoid driving it was wait for the ignition coils til last and just line up its completion based off of difficulty and access points. To get the job for the most part in a few hours and just stock up on the parts. Still had some small vap leaks from underneath the coolant thermostat under the expansion tank, so i was trying to seal it with like some permanent fixture like JBWELD LET IT SET then some marine water adhesive that can withstand a high pressure and an excessive amount of heat in case of emergency. Not like gorilla glue or nothing like that, but better, more durable…. that way if any issues were to happen i would just got ahead and swop out the expansion tank with a new mount the whole shibang at onetime with out the radiator, the origins of the discovered problem was underneath the expansion tank that was in it, there was no coolant level sensor, which i thought was realy retarded so i was keen with the oil when i swopped it out for the first time, perfect smell all black synthetic oil no grey color or sign if a blown head gasket , the motors pretty protective and thats why i like the bimmer conversion, So as I was driving the 325 ci racing the flood because i didnt Wana lose the investment in a natural disaster The first 17 miles was sweet longest I’ve ever driven it. Was pushin about 85 riding clean I got to about 25 miles in and Thermostat on the dash peaked to the red , kept driving and it stalled out with the thermometer flatlined,…pushed it through the intersection safely had a tow pull up the night after got it to the safe destination, now I’m wondering if after that excessive heating took place if the ignition coils completely went out or lost spark…I’m still able to turn over and hear it crank but it’s not starting, also whenever I would connect the MAF the idle would go completely off so I know I wanna do the MAF maybe up the intake with the distributors maybe get its first new battery. It drives like it probably did in 2007 128k miles on it, I didn’t wanna have to drive it and rush the patch. But another thing is that the heater doesn’t work so I’m tryna figure out if I needa go heater core, I could always just get a plug in heater for inside portable i looked a couple of those up so I wouldn’t have to hit the cars system with the wattage just the battery maybe. Any feedback is greatly appreciated.

  12. Congratulations on successfully resolving the issue. i have a e46 325i with motor 330i it has sporadically error INPA 211 valve closed idling, already changed the valve, checked all the connections. But still the Traction Light and EML turn on when I’m downshifting below 2500RPM. when I take my foot off the accelerator, for example an intersection or speed camera

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