Never-ending EML/limp mode problems

[Norocehcap]

I have been getting an EML, CEL and limp mode for about a year at random and very frequently, sometimes the car works perfectly, sometimes I can feel a slight miss and sometimes it will throw an EML, CEL and go into full limp mode and limit power and RPMs, I can’t drive the car anywhere out of fear because it happens so frequently. I have just got INPA installed and scanned the car but here is what has been done so far.

Previously I was using a Schwaben/Foxwell BMW scanner and getting codes
"P1637- throttle valve position control deviation"
"P0121- throttle/pedal position sensor/switch “A” circuit range/performance"
"P0221- throttle/pedal position sensor/switch “B” circuit range/performance."

I have replaced both TPS under the hood, throttle actuator, throttle pedal, MAF and I have cleaned the IAC and ITB’s, also the clamps on the airbox are not contacting anything when throttle is applied and ITBs open. I have also checked the ECU for water damage and found none, nor any corrosion inside or outside, I was expecting to find a little water since it seems to do it slightly more often when it rains but it does it in the dry as well.

I have scanned the car with INPA today and it read
"120 Throttle Potentiometer Comparison"
"118 Throttle Potentiometer 1"
"119 Throttle valve Potentiometer 2"
"121 Both Throttle Valve Potentiometers"

When I scan the car everything is in German so I took pictures I will attach and used google translate. I admit I don’t really know how to use INPA that well and if there are any other scans I should be doing please let me know. I am at a loss, I don’t know what to do next, I have been having this problem for about a year and cannot drive the car because of it. Please help me I am out of ideas, thanks!

[sapote]

Did you do throttle Calibration after replacing parts?

[Norocehcap]

Did you do throttle Calibration after replacing parts?

I did the calibration where you press the throttle to the floor, put key to position 2, wait 10 seconds, turn the key to position 0 and then release the pedal. I saw a few different methods to calibrate, should I try something else?

[M3fanatic580]

Following.

[BL92]

https://www.youtube.com/watch?v=R5eLlYXROlM

[oceansize]

Look at post 6, perhaps time to check that the new TPS are indeed good.

https://nam3forum.com/forums/forum/main-forum/e46-2001-2006/166685-accelerator-pedal-code

[Norocehcap]

Look at post 6, perhaps time to check that the new TPS are indeed good.

https://nam3forum.com/forums/forum/m...tor-pedal-code

I'm on my 3rd set of TPS, first I switched both to VNE, when that didn't fix it I bought Genuine BMW TPS just to be sure, also the new Pierberg throttle body actuator had a new TPS on it so that has been changed another time as well, ugh lol. I am also on my 3rd throttle pedal, bought a new one, didn't fix the problem and sent it back to FCP and got another. I will read through that thread and see what info is there. Thanks for the suggestions people, I really have no clue where to go from here.

[Norocehcap]

I have also had my DME tested by ECU Pro and it tested good, then I had them clone my DME and make another, I never got around to using that DME because I actually thought I solved this problem about about a month or 2 ago. When I installed the new DME just to make sure it worked and keep it as a spare I could feel the car doing the same thing as my original DME where it sometimes feels like it's missing so no real improvement. I only drove the car for 30 min though, not long, and never got an EML but could feel it missing still. I would have liked to use the new DME for longer to see if there would be any difference but that DME throws code 154 crankcase ventilation everytime the car is started for some reason and my original DME has never thrown that code. I have contacted them waiting for a response. Should I put that DME back in the car and just disregard code 154 and see if/when it throws an EML, will code 154 have any effect on the TPS/EML issues?

[Norocehcap]

I have another question about the DME clone. I contacted The ECU Pro about their replacement DME throwing code 154 and mine does not and they told me flat out I'm out of warranty and they wont help, understandable out of warranty, I knew I would probably not get a refund but at least I could keep it as a spare just in case it was needed, the DME is suppose to be an exact copy of mine, why does this DME throw code 154 and mine does not? Does anyone know anyone who can fix this problem with the DME, wasted $1500 on a DME that throws a code immediately on start up, kinda stings lol. Its one thing to waste money on a part not needed, its worse that the DME throws a CEL and its not even useful as a spare.

[sapote]

I did the calibration where you press the throttle to the floor, put key to position 2, wait 10 seconds, turn the key to position 0 and then release the pedal. I saw a few different methods to calibrate, should I try something else?

Use inpa to do throttle calib.

[Norocehcap]

Use inpa to do throttle calib.

Thank you, I just did that, I will report back tomorrow after a test drive.

[332]

Thank you, I just did that, I will report back tomorrow after a test drive.

This is the exact same problem I'm having, I swapped my s54 into a new chassis and I've been hunting this same issue. I've done all the things you have replaced all the tps sensors, car will rev while not moving to redline. However, once I get the car moving and try to go full throttle it hits limp mode/eml/cel etc. I read in a thread, it could be 02 related. Or even a rear wheel speed sensor, I had this issue on my 330i. It turned out to be a loose ground in the engine bay, on that car. B/c once the engine was revving high, the motor was moving just a bit to make the ground not contact and threw a eml/limp mode. Keep us posted!!

[Norocehcap]

This is the exact same problem I'm having, I swapped my s54 into a new chassis and I've been hunting this same issue. I've done all the things you have replaced all the tps sensors, car will rev while not moving to redline. However, once I get the car moving and try to go full throttle it hits limp mode/eml/cel etc. I read in a thread, it could be 02 related. Or even a rear wheel speed sensor, I had this issue on my 330i. It turned out to be a loose ground in the engine bay, on that car. B/c once the engine was revving high, the motor was moving just a bit to make the ground not contact and threw a eml/limp mode. Keep us posted!!

This problem seems unsolvable ugh. I drove the car for a week straight and had no issues until a few days ago it came back and for me it seems to happen completely at random except for 1 thing, rain seems to make to happen more often but it is not limited to rain and not every time it rains, I drove the car in the rain for about an hour a week ago and had zero issues. I have even had this car at Lime Rock Park sitting at high rpms for laps at a time and it was faultless all day . I have never had a code for o2 sensors or wheels sensors, however both of the wiring for those parts would be exposed to water during rain, maybe I should look there but like I said I can drive in the rain and it will be fine. I have also checked the DME and its bone dry, I noticed a small amount of water got past the weatherstrip where the hood meets the cowl but the DME box and the DME itself was dry, I have since slid the weather stripping over to make a more complete seal, maybe there is some wiring underneath the DME box that got wet, maybe the ground wire is the problem like your 330i. I have been trying to solve this problem for a long time on my own. I have replaced every part pertaining to TPS figuring if everything was new it would have to work lol it did not, it will go away and then bam its right back, that's why I made this thread asking the community for help. I have read soooooooooo many EML posts and 9 times out of 10 they have no solution. When/if I ever figure this out I will 100% post the solution. I am almost getting to the point to bringing it to a specialist maybe Rouge Engineering, they did my big 3, but I am worried it will be fine while they have it since its intermittent and it only throws TPS codes which i have changed multiple times. Thanks for the insight, this is extremely frustrating and I feel you pain.

[332]

This problem seems unsolvable ugh. I drove the car for a week straight and had no issues until a few days ago it came back and for me it seems to happen completely at random except for 1 thing, rain seems to make to happen more often but it is not limited to rain and not every time it rains, I drove the car in the rain for about an hour a week ago and had zero issues. I have even had this car at Lime Rock Park sitting at high rpms for laps at a time and it was faultless all day . I have never had a code for o2 sensors or wheels sensors, however both of the wiring for those parts would be exposed to water during rain, maybe I should look there but like I said I can drive in the rain and it will be fine. I have also checked the DME and its bone dry, I noticed a small amount of water got past the weatherstrip where the hood meets the cowl but the DME box and the DME itself was dry, I have since slid the weather stripping over to make a more complete seal, maybe there is some wiring underneath the DME box that got wet, maybe the ground wire is the problem like your 330i. I have been trying to solve this problem for a long time on my own. I have replaced every part pertaining to TPS figuring if everything was new it would have to work lol it did not, it will go away and then bam its right back, that's why I made this thread asking the community for help. I have read soooooooooo many EML posts and 9 times out of 10 they have no solution. When/if I ever figure this out I will 100% post the solution. I am almost getting to the point to bringing it to a specialist maybe Rouge Engineering, they did my big 3, but I am worried it will be fine while they have it since its intermittent and it only throws TPS codes which i have changed multiple times. Thanks for the insight, this is extremely frustrating and I feel you pain.

Our issues might be the same, but I doubt it. Mine happens every time no matter what, once the car is under load and the rpm is at X,XXX.

[Norocehcap]

Our issues might be the same, but I doubt it. Mine happens every time no matter what, once the car is under load and the rpm is at X,XXX.

All the information we can gather might be helpful to us or others in the future, I am keeping what you said in mind regardless, might spark something in my brain and help figure it out.