e46 M3 Idle Issue - Need Help

[special77]

Hi everyone, long time lurker to this forum but just signed up for an account hoping to get some guidance for my 2003 e46 M3 vert SMG to manual conversion.

I have had a hunting or surging idle ever since I bought this car about a year ago. It seems to idle kind of high (around 900 which I hear is fairly normal for this car) but will surge up to 1200 and then bog down to 4-500. On rare occasions the car will occasionally stall. I can prevent this by blipping the gas when I feel the RPMs getting too low. No issues otherwise, power seems to be all there. I have taken the car to 2 mechanics who are stumped. It has has had a smoke test (negative for leaks), throttle bodies cleaned, ICV cleaned and then subsequently replaced, new TPS, fuel pump and filter checked, and spark plugs replaced.

There is one code that keeps coming back in the DME immediately after clearing:
Fault code 80 schalterkette kraftschluss which I understand is related to the clutch position sensor.

I checked at the clutch pedal and it looks like I do have the brown clutch position sensor with part number ending in 700.
The wiring looks ok too based on some of the SMG to manual guides on this site with a wire going into connector/pin 20 on the DME.
Also, I confirmed the correct operation of the switch in INPA. (status grip switch off with clutch out and on with the clutch in).

Would it be worthwhile to replace the clutch position sensor even though it is functioning normally according to INPA? Any other ideas or further guidance?

Thanks everyone in advance for any help!

[2003wmb]

Hi everyone, long time lurker to this forum but just signed up for an account hoping to get some guidance for my 2003 e46 M3 vert SMG to manual conversion.

I have had a hunting or surging idle ever since I bought this car about a year ago. It seems to idle kind of high (around 900 which I hear is fairly normal for this car) but will surge up to 1200 and then bog down to 4-500. On rare occasions the car will occasionally stall. I can prevent this by blipping the gas when I feel the RPMs getting too low. No issues otherwise, power seems to be all there. I have taken the car to 2 mechanics who are stumped. It has has had a smoke test (negative for leaks), throttle bodies cleaned, ICV cleaned and then subsequently replaced, new TPS, fuel pump and filter checked, and spark plugs replaced.

There is one code that keeps coming back in the DME immediately after clearing:
Fault code 80 schalterkette kraftschluss which I understand is related to the clutch position sensor.

I checked at the clutch pedal and it looks like I do have the brown clutch position sensor with part number ending in 700.
The wiring looks ok too based on some of the SMG to manual guides on this site with a wire going into connector/pin 20 on the DME.
Also, I confirmed the correct operation of the switch in INPA. (status grip switch off with clutch out and on with the clutch in).

Would it be worthwhile to replace the clutch position sensor even though it is functioning normally according to INPA? Any other ideas or further guidance?

Thanks everyone in advance for any help!

Did you ever get the idle issue fixed? I have the same issue. After the conversion SMG to 6M the vehicle was codded but the engine stalls. I have the right clutch module 700, my cruise control works and the engine starts when the clutch pedal is pressed down. (depressed) After the vehicle warms up it stalls when I come to a stop. All the wiring to the DME and EWS is correct.

[3state]

I know this is an old thread but I may have shed some light on this. I have a s54 swapped wagon that was an automatic originally. When I first bought it, I noticed that it would stall intermittently after deceleration in neutral or clutch depressed. The donor transmission was an actual manual 420g which still had had the gear recognition switch installed. To my surprise, it wasn't hooked up. I bought a fuel injector pigtail from Amazon and ran the wires up to the DME where the clutch switch was directly wired into the DME as I believe most SMG to manual swaps are. I wired the gear Recognition Switch in series of the clutch switch wire at pin 20 of the x60002 connector and flashed in a stock manual bin file. THE STALLING COMPLETELY WENT AWAY!.

[bmwfnatic]

I know this is an old thread but I may have shed some light on this. I have a s54 swapped wagon that was an automatic originally. When I first bought it, I noticed that it would stall intermittently after deceleration in neutral or clutch depressed. The donor transmission was an actual manual 420g which still had had the gear recognition switch installed. To my surprise, it wasn't hooked up. I bought a fuel injector pigtail from Amazon and ran the wires up to the DME where the clutch switch was directly wired into the DME as I believe most SMG to manual swaps are. I wired the gear Recognition Switch in series of the clutch switch wire at pin 20 of the x60002 connector and flashed in a stock manual bin file. THE STALLING COMPLETELY WENT AWAY!.

Yup, you either have to wire it in properly like you did, or change your tune properly to let the car know that there is no GPS, otherwise you get the code 80 and the stalling, just putting this here for future readers.

[Elvin123]

Any updates on this? Currently going through the same issues on my manual swap. Stalling when coasting in neutral. I have a good clutch switch with the part number ending in 700. Seems to be working on inpa. I also coded the gps out. No luck.