[michaelbarton3077]

Hello,

First time poster here. I've got a 2000 323i that is now in "limp" mode, with the EML and DSC lights on. Any help would be greatly appreciated, as I've poured through countless forums and still do not have an answer.

History:
The car originally presented with the SES light on and a code(s) (can't remember which) that pointed to a vacuum leak. So I decided to replace the entire CCV system and all vacuum lines. I did it the "right" way and removed the intake. However, when putting it back together I forgot which vacuum lines went where. I think I got all the vacuum lines correct, but don't know for sure as I couldn't find a diagram anywhere online.

Once I got the car all back together, I tried to start it. The engine would turn over, but refused to start. After digging around on forums, I discovered I switched two of the wiring harness plugs. This caused a 30amp fuse to blow. After replacing the fuse, the car started up.

At this point the engine refused to go over 3000rpm and by all indications was in "limp" mode with the EML and DSC lights on. Using INPA, I cleared all codes and reset the adaptations. When I started the car, all the lights went off. However, as soon as I pushed the pedal a little, the lights came back and the car was back in limp mode.

Following several posts, I used a multimeter to test continuity on the wires going from DME to the MDK; test PASSED. According to the manual, this indicates a bad MDK. So, I ordered a USED one off ebay. After putting on the "new" MDK, the problem persisted.

I once again turned to the forums. One suggested that even with proper continuity in the wiring harness, it is possible the connector has cracked/broken. So I, stupidly, decided to order a brand new wiring harness (as mine had tears in the sheathing and broken connectors in other locations). After installing the new harness, I still have the same issues...

Current Status:
EML and DSC lights illuminated on the dash
INPA reads:
169 MDK output stage control after diagnostic failure

Error frequency: 2
Logistic counter: 40

Engine speed 864.00 1/min
temperature intake air 25.50 Grad C
Battery Voltage 13.67 V
temperature cooling water 59.25 Grad C
appear before (rel.) 0.00 h

114 avtivate motor throttle valve

Error frequency: 1
Logistic counter: 40

actual valve throttle poti 5.62 Grad DK
nominal data Throttle valve 0.00 Grad DK
temperature intake air 30.75 Grad C
Battery Voltage 13.77 V
appear before (rel.) 0.00 h

I am at a loss. I love this car, but can't justify putting much more into it. She's 20 years old with 210k miles. If anyone has any suggestions, please let me know.

Thank you for your time.

 

[alcarazdiego10]

Sound like clog catalytic converter, you loss power over 3200-4500 rmp and sometime its there n sometimes it just drops into limp mode. Does the car burn oil? Probably the cause of your cat getting clogged.

Sent from my SM-G973U using Tapatalk

 

[Bali]

This is a very common story when throwing parts at a problem without first diagnosing the root cause. I never replace a part until my tests prove it***8217;s defective, except for preventative maintenance.

Here is what I would do:
- use INPA (F5 Status) to see all the sensor values (both position and voltage) on the accelerator pedal and throttle valve
- Google those trouble codes to gain a better understanding of what they actually mean
- compare movement and resistance values of both throttle valves
- pull the DME connectors and carefully inspect pins for damage or fluid infiltration

 

[michaelbarton3077]

- I previously verified through INPA that all position and voltage sensors for the pedal and throttle were reporting. However, I do not know what "correct" values would look like.
- My previous Google research is what led to the wire pin-outs and the determination of a bad MDK.
- I will try to do this and report back. Any idea what "correct" values would be?
- I will take a look at this as well. I previously inspected for water damage, but will inspect more closely for damaged pins.

 

[Bali]

- I previously verified through INPA that all position and voltage sensors for the pedal and throttle were reporting. However, I do not know what "correct" values would look like.
- My previous Google research is what led to the wire pin-outs and the determination of a bad MDK.
- I will try to do this and report back. Any idea what "correct" values would be?
- I will take a look at this as well. I previously inspected for water damage, but will inspect more closely for damaged pins.

Each gauge in INPA is a scale with upper and lower bounds, so it’s easy to see if signals are in range or not. Accelerator pedal and MDK both have two sensors whose voltages go in opposite directions, so DME can detect a bad one and use the other.

See example screen shots here: https://bimmerprofs.com/diagnostics-of-ms43/

 

[michaelbarton3077]

Each gauge in INPA is a scale with upper and lower bounds, so it’s easy to see if signals are in range or not. Accelerator pedal and MDK both have two sensors whose voltages go in opposite directions, so DME can detect a bad one and use the other.

I looked at the connections on the DME... they all look pristine.

I took measurements for both MDKs and created a Google Sheet with the readouts from INPA. All measurements were taken with the engine off. For each throttle body, I:
- turned ignition on
- used INPA to monitor DKP-angle at WOT throttle
- adjusted throttle cable to ensure DKP-angle was between 80-84 degrees
- turned ignition off for :30 sec
- turned ignition on
- read codes with INPA
- cleared codes with INPA (SES, EML, and DSC turned off)
- cleared adaptations
- pressed pedal to WOT x4 times (SES, EML, and DSC turned back on)
- turned ignition off
- started car and verified issue was still present

Link to my Google Sheet is below:
https://docs.google.com/spreadsheets/d/1miFPN4sr8TacyyUGj9DAmUJ_hVnoXo1H7zqo-aIKoRk/edit?usp=sharing

 

[Anticdubai]

Check condition of MAF sensor. It is common issue and usually reading codes sends you in wrong direction. read MAF performance. Not just connect-disconnect.

 

[Anticdubai]

Sound like clog catalytic converter, you loss power over 3200-4500 rmp and sometime its there n sometimes it just drops into limp mode. Does the car burn oil? Probably the cause of your cat getting clogged.

Sent from my SM-G973U using Tapatalk

clogged cat doesn't appears overnight, and usually you can feel significant power loss on any revs. It doesn't drop codes. cats are possibly bad but that isn't a root of a problem.

 

[alcarazdiego10]

clogged cat doesn't appears overnight, and usually you can feel significant power loss on any revs. It doesn't drop codes. cats are possibly bad but that isn't a root of a problem.

There not completely clog there getting there. His going to have this issue on and off... he replace the vanos or rebuild it, n just throw part at it... pick up a set at pick n pull for 75 buck say there exhaust manifold. N just humor me for 75 bucks

Sent from my SM-G973U using Tapatalk

 

[michaelbarton3077]

Check condition of MAF sensor. It is common issue and usually reading codes sends you in wrong direction. read MAF performance. Not just connect-disconnect.

I'll take a look at the MAF tonight. However, I noticed that after clearing the codes and turning the ignition off/on. The lights are off. BUT, without starting the engine, the codes will return if I depress the gas pedal. So whatever is setting the codes off has to be engaged with the engine off, right?

 

[michaelbarton3077]

There not completely clog there getting there. His going to have this issue on and off... he replace the vanos or rebuild it, n just throw part at it... pick up a set at pick n pull for 75 buck say there exhaust manifold. N just humor me for 75 bucks

Sent from my SM-G973U using Tapatalk

I noticed that after clearing the codes and turning the ignition off/on, the lights are off. BUT, without starting the engine, the codes will return if I depress the gas pedal. So whatever is setting the codes off has to be engaged with the engine off, right?

 

[Bali]

Just read through this thread again and it occurred to me the issue could be internal to the DME itself. You've already replaced the TB and wiring harness, so that's basically what's left.

The spreadsheet numbers for both TBs all seemed fairly similar to eachother.

I would also pull and clean the associated fuses. Any voltage drop could play havoc with the detected throttle positions.

Would also be a good idea to do the wiggle wire test. With ignition on, and looking at the throttle position values in INPA, wiggle/move around the wiring harness and connectors looking for any change in voltage.

These 323/328 TBs are a weird hybrid of cable and electronics, as you've seen by now. They are "drive-by-wire" like the 325/330 except the accelerator pedal potentiometers are inside the TB and actuated via a cable, instead of at the pedal itself.

It is NOT clogged cats or a bad MAF! Be careful who you listen to and what they say.

 

[michaelbarton3077]

Just read through this thread again and it occurred to me the issue could be internal to the DME itself. You've already replaced the TB and wiring harness, so that's basically what's left.

The spreadsheet numbers for both TBs all seemed fairly similar to eachother.

I would also pull and clean the associated fuses. Any voltage drop could play havoc with the detected throttle positions.

Would also be a good idea to do the wiggle wire test. With ignition on, and looking at the throttle position values in INPA, wiggle/move around the wiring harness and connectors looking for any change in voltage.

These 323/328 TBs are a weird hybrid of cable and electronics, as you've seen by now. They are "drive-by-wire" like the 325/330 except the accelerator pedal potentiometers are inside the TB and actuated via a cable, instead of at the pedal itself.

It is NOT clogged cats or a bad MAF! Be careful who you listen to and what they say.

Is there any way to verify the DME is bad? Is there any way to fix/repair without a costly dealership replace/coding?

 

[Bali]

Is there any way to verify the DME is bad? Is there any way to fix/repair without a costly dealership replace/coding?

Sure, all depends on your electronics skills. The easy test is to drop in a good used DME, clear adaptations, and test.

There are DME repair houses out there. But since the MS42 DME has been unlocked, you can now buy a used one and program it to work on your car.
https://www.ms4x.net/index.php?title=Main_Page

I’ll say this again: I wouldn’t replace ANY part until I KNOW it’s bad.

Which electrical connectors did you originally mess up?

 

[michaelbarton3077]

Sure, all depends on your electronics skills. The easy test is to drop in a good used DME, clear adaptations, and test.

There are DME repair houses out there. But since the MS42 DME has been unlocked, you can now buy a used one and program it to work on your car.
https://www.ms4x.net/index.php?title=Main_Page

I***8217;ll say this again: I wouldn***8217;t replace ANY part until I KNOW it***8217;s bad.

Which electrical connectors did you originally mess up?

Regarding my electrical skills, I'm a DIYer that learns very quickly. Also, at this point the car is useless and I have a second vehicle. So, if you know how I can troubleshoot or can point me to a resource, I'll gladly give it a go. I'll take a look at that website tonight.

There are two connectors that are keyed the same. I can't recall which ones, but they both have two slots for contacts. But one connector only used one of the two contacts.

Lastly, thank you everyone for your help.

 

[michaelbarton3077]

Sure, all depends on your electronics skills. The easy test is to drop in a good used DME, clear adaptations, and test.

There are DME repair houses out there. But since the MS42 DME has been unlocked, you can now buy a used one and program it to work on your car.
https://www.ms4x.net/index.php?title=Main_Page

I’ll say this again: I wouldn’t replace ANY part until I KNOW it’s bad.

Which electrical connectors did you originally mess up?

I verified I have the MS42 DME. I also popped the DME open and found a couple indicators of a partially fried DME... please see the photos at the below link. Once picture shows a completely blown component and the other photo shows a circuit path that has discoloration.

So, is the next step to attempt to read my configuration and attempt to save it so I can flash a used DME with my current configuration? Does that blown component house any configurations? or would I be able to read my entire configuration?

https://photos.app.goo.gl/WKcEHU7E7TSCSb9U6

 

[Bali]

Repair or replace the DME.
Read the ms4x.net website for how to clone your DME to a used one.

 

[michaelbarton3077]

Repair or replace the DME.
Read the ms4x.net website for how to clone your DME to a used one.

I've reviewed ms4x.net and other related sites. Using MS4X Dev Group Flasher, I was able to read/save the 512KB file. My MS42 has firmware version 0110CA.

My questions now are:
1) Do I need to get another 0110CA MS42 or will any fw version suffice?
2) Do I simply plug in the new (used) MS42 and write my 512KB file to it and be done?
3) Since this is a clone and not a tune, I don't need to worry about definition files and other stuff, right?