[LeMoo]

I’ve been digging and haven’t found a solution that reflects my cars issue..hoping someone has heard of this.

The car has high miles (200k) but all wear parts have been replaced. Brakes operate as they should, no codes present, all is well, etc. I should add, ABS & DSC are (were) functioning correctly frequently tested in CO snow.
Only “mod” is a Kassel tune with downstream O2 sensors and SAP deleted.

Brake & ABS lights came on randomly while driving. Coming to a stop on dry road (no slippage) the ABS pump cycled a few times. It then did it a few other times so I figured it was probably just dying so I unplugged the pump knowing all ABS/DSC were to be disabled. Turns out you lease speedo too.

Here’s the weird part: when I got the car (pre-tune) I noticed that the throttle would hang on pretty significantly once letting off throttle. It also seems a little sluggish but thats fine by comparison. By “hang on“ I mean a full second before it stops accelerating on its own. I’ll say that again..it continues to accelerate for a full second AFTER I remove throttle input. Manageable on dry roads, snow covered can get interesting real quick.
I thought the tune aight take care of it and thought it was improved but still needed work. After chatting with Kassel, I sent the DME back for a revision. No change throttle response.

Back to the ABS pump: when I unplugged it and drove away..I now had crisp throttle response & zero hang...in short, exactly as it should be. I called Kassel and told them what I found, they suggested to start at the ABS pump/module so I did.

In prep I pulled all the wheel sensors to check and make sure they weren’t covered in whatever, cleaned off the minimal junk and reinstalled. The ABS module in mine is 2 piece: the plastic module(dry) that bolts to the distribution block(wet). Seemed like the easiest thing would be to swap the module first before replacing the distribution block and having to open/bleed the system. So, I finally found a module and swapped it with zero change, i.e. it still hangs on throttle when plugged into the ABS module. So, we’re back to being unplugged.

Seems unlikely that it would be something inside the distribution block that would cause what must be an incorrect input to the DME making it respond by hanging on the throttle. I don’t want to just start throwing parts at it, already wayyyyyyyyy over budget on rebuilding this thing Lol.


Please share thoughts or point me in a direction. Also, a BMW tech looked at it and couldn’t make sense of it but didn’t have a BMW scan tool really look. It may just have to go to the stealership..

 

[Bali]

Set up BMW Standard Tools and use INPA to view the DSC/ABS trouble codes and live data.
How to Install BMW Standard Tools
That will give you the needed insight on the DSC behavior to troubleshoot this.

You can read up on the E46 traction control system in this document.

E46 Traction and Stability Control.pdf

drive.google.com

Know that the E46 XI models use a Bosch 5.7 DSC module (same as E39) that often needs rebuilding. You need further diagnosis before going that route, but keep it in mind.

 

[LeMoo]

Set up BMW Standard Tools and use INPA to view the DSC/ABS trouble codes and live data.
How to Install BMW Standard Tools
That will give you the needed insight on the DSC behavior to troubleshoot this.

You can read up on the E46 traction control system in this document.

E46 Traction and Stability Control.pdf

drive.google.com

Know that the E46 XI models use a Bosch 5.7 DSC module (same as E39) that often needs rebuilding. You need further diagnosis before going that route, but keep it in mind.

Good to know re: module rebuild
Thanks 🍻

 

[txl]

I had a similar throttle hang on my 325xi 09.2001 when I acquired it three years ago. Was fixed with DME software update. It had original version and I updated it to the latest.

 

[TobyB]

So the car keeps accelerating even if you tap the brake?

t

 

[Bali]

A few questions:

1. I see this is a 5-speed MT. Was it originally auto trans and then later MT swapped?
2. Does the rev hang occur after you use the DSC button to disable traction control?
3. Have you tried stock DME software or another DME with EWS delete?

 

[LeMoo]

So the car keeps accelerating even if you tap the brake?

t

Yep, for close to a full second. Doesn’t do it with ABS pump/module unplugged.

 

[LeMoo]

A few questions:

1. I see this is a 5-speed MT. Was it originally auto trans and then later MT swapped?
2. Does the rev hang occur after you use the DSC button to disable traction control?
3. Have you tried stock DME software or another DME with EWS delete?

1)original 5spd car
2) yes
3) I ran it with the stock software for a short while before starting all the neglected maintenance and repairs. I opted to send Kassel my DME because it was another $3-400 to program another DME with EWS delete. They’ve had it twice, any reason to think that they wouldn’t have caught a software issue?

 

[LeMoo]

I had a similar throttle hang on my 325xi 09.2001 when I acquired it three years ago. Was fixed with DME software update. It had original version and I updated it to the latest.

Any reason to think Kassel wouldn’t have caught that it required software update?

 

[TobyB]

Easy to check- MS4X Wiki

download the flasher, and read your ECU. -69 is the latest.

rev hangs aren't normal, though- I've run a half- dozen different
software versions, and never had it. I HAVE found that a bad ECU
will manifest in different ways based on the software version-
what was a 'bad CPS' turned into 'throttle adaptation errors'
when a -34 ECU was updated to -69... I'm making a LARGE assumption
that the particular ECU has a bad EEPROM cell that's used differently by
different versions.

In your shoes, I would read your ECU in bootmode, dump it to another,
and try that. ECUs are cheap in the junkyards now, and the oldest are
of drinking age, so I suspect memory loss or corruption is going to become more common...

You can also flash a clean, EWS- deleted patch and try that, too. It fixed the
'CPS Error' car...

The ECU is (rightly) phobic of throttle hanging- the pedal- vs- RPM routines
SHOULD be pitching a huge fuss because the engine revs aren't matching
what the pedal's asking for, and the car SHOULD be dropping to idle,
blinking like a Christmas tree.
Even if you just have a sticky idle control valve.

Thus, I'd rule out the ECU.

And I don't know what Kassel does, but the 'bad CPS' ECU didn't look
like it had ANY problems using PASoft, INPA, or any of the flashing tools.
It only misbehaved when connected to a running car. And then, it insisted
that the CPS was bad. After reflashing to -69, it insisted that the pedal was bad.
Even though IT was the only variable.

just my experience with this,

t
electronic alzheimer's

 

[txl]

Any reason to think Kassel wouldn’t have caught that it required software update?

Well, I cannot answer that. I don't know.

What I have done is to update my DME version as per BaliDawg's thread with WinKFP:

Need a DME or EGS flash update?

What? I have written guides (see links below) to show you how to update the software in your DME (engine control module) or EGS (automatic transmission control module) to the latest BMW factory version for free using WinKFP. Why? I recommend every car be updated to the latest. There are three...

www.e46fanatics.com

I had version 7516444 and updated it to 7564474. This versioning is not the same as used on MS4X Wiki and referred to by TobyB.

 

[Effduration]

Does your cruise control work properly?

In my manual swapped and manual coded '03 530i, I had a rev hang until the cruise control switch was properly connected. Took me a while to figure it out.

Others in the E46 and E39 world have reported that when the cruise switch was disconnected, it resulted in a rev hang.
It apparently provides an input to the DME.

 

[LeMoo]

Does your cruise control work properly?

In my manual swapped and manual coded '03 530i, I had a rev hang until the cruise control switch was properly connected. Took me a while to figure it out.

Others in the E46 and E39 world have reported that when the cruise switch was disconnected, it resulted in a rev hang.
It apparently provides an input to the DME.

It seemed to work fine when the ABS module was connected..

Waiting on a window for my BMW tech buddy to get it in and poke around.

 

[Matt46]

I’ve been digging and haven’t found a solution that reflects my cars issue..hoping someone has heard of this.

The car has high miles (200k) but all wear parts have been replaced. Brakes operate as they should, no codes present, all is well, etc. I should add, ABS & DSC are (were) functioning correctly frequently tested in CO snow.
Only “mod” is a Kassel tune with downstream O2 sensors and SAP deleted.

Brake & ABS lights came on randomly while driving. Coming to a stop on dry road (no slippage) the ABS pump cycled a few times. It then did it a few other times so I figured it was probably just dying so I unplugged the pump knowing all ABS/DSC were to be disabled. Turns out you lease speedo too.

Here’s the weird part: when I got the car (pre-tune) I noticed that the throttle would hang on pretty significantly once letting off throttle. It also seems a little sluggish but thats fine by comparison. By “hang on“ I mean a full second before it stops accelerating on its own. I’ll say that again..it continues to accelerate for a full second AFTER I remove throttle input. Manageable on dry roads, snow covered can get interesting real quick.
I thought the tune aight take care of it and thought it was improved but still needed work. After chatting with Kassel, I sent the DME back for a revision. No change throttle response.

Back to the ABS pump: when I unplugged it and drove away..I now had crisp throttle response & zero hang...in short, exactly as it should be. I called Kassel and told them what I found, they suggested to start at the ABS pump/module so I did.

In prep I pulled all the wheel sensors to check and make sure they weren’t covered in whatever, cleaned off the minimal junk and reinstalled. The ABS module in mine is 2 piece: the plastic module(dry) that bolts to the distribution block(wet). Seemed like the easiest thing would be to swap the module first before replacing the distribution block and having to open/bleed the system. So, I finally found a module and swapped it with zero change, i.e. it still hangs on throttle when plugged into the ABS module. So, we’re back to being unplugged.

Seems unlikely that it would be something inside the distribution block that would cause what must be an incorrect input to the DME making it respond by hanging on the throttle. I don’t want to just start throwing parts at it, already wayyyyyyyyy over budget on rebuilding this thing Lol.


Please share thoughts or point me in a direction. Also, a BMW tech looked at it and couldn’t make sense of it but didn’t have a BMW scan tool really look. It may just have to go to the stealership..

I have the exact same situation happening to me too. I sent off my module to have it rebuilt and when it came back and plugged it in like you did it still continued to accelerate for a second or so but not as much as it did before the rebuild. Wondering if you’ve found anything out or not

 

[LeMoo]

Researching this still as I have an issue with the DME hanging throttle for 1-2 seconds after lifting off. It’s definitely not the flywheel or some other mechanical snafu. How I know? If I unplug the abs module, which takes away wheel speed sensors, dsc, & and speedo, throttle response is instant on/off.
DME has a Kassel tune that they’ve tried to tune out the hang as well as updating firmware and resetting all adaptations.
any thoughts??
Clutch switch, cruise control issue??

 

[Bali]

Search the manual trans swap threads for “throttle hang”.

 

[NZ00Z3]

Is this in your 2002 325XiT?

Do you have the traction control, ABS or Brake warning lights up?

Have you scanned the ABS module for trouble codes? You'll need a scanner with BMW software to do this. How to Install BMW Standard Tools

If you go back to the original BMW DME tune, does the problem persist?

 

[alan53]

How old are the pre cat o2 sensors ? Mine caused this i only found out when i changed them doing routine maintenance.

 

[LeMoo]

Search the manual trans swap threads for “throttle hang”.

Its not a swap, factory 5spd.

Is this in your 2002 325XiT?
Yes

Do you have the traction control, ABS or Brake warning lights up?
No. Traction control works as it should. Throttle hang disappears though when ABS module unplugged.

Have you scanned the ABS module for trouble codes? You'll need a scanner with BMW software to do this. How to Install BMW Standard Tools
Yes and no codes.

If you go back to the original BMW DME tune, does the problem persist?

It existed before it was tuned, continues with tune and revision of tune.

How old are the pre cat o2 sensors ? Mine caused this i only found out when i changed them doing routine maintenance.

O2 sensors are new.

 

[NZ00Z3]

Do you have the traction control, ABS or Brake warning lights up?

Have you scanned the ABS module for trouble codes? You'll need a scanner with BMW software to do this. How to Install BMW Standard Tools

Any update on the above?

If it stops hanging when you disconnect the ABS, then there is something going on with the data the ABS and DME are sharing. ABS trouble codes will be clues.