MoTeC Global Forum

Hello MoTec-Team,

We have an Audi FSI engine (2 litre, modifierd for CNG) running with the M800 on a test rig. At idle, everything seems to be fine, the engine is running nice and smooth. Leaving the idle, ref sync problems occure (3. Errors):
1. Ref Signal
2. Ref Noise Ar
3. Sync Signal.
Missfire happens, and the ref sync capture shows an extended sync pulse (could't upload the fiel, therefore I took a picture).
Ref signal by Hall sensor and gear ring with 60 teeth, sync by Hall sensor and one defined pulse. The ref/sync configurations are also attached.
Hopefully someone can help me. Thanks in advance.

Hi
If you use 60 teeths you MUST use a magnetich sensor.
If youhave 4 teeths you can use a hall sensor.


AF

Arve Flaat wrote:Hi
If you use 60 teeths you MUST use a magnetich sensor.
If youhave 4 teeths you can use a hall sensor.


AF

Hello Arve,

do you have any explanation why a hall sensor can't be used ? Thanks.

Regards,
Chris

Amigo_88 wrote:

Arve Flaat wrote:Hi
If you use 60 teeths you MUST use a magnetich sensor.
If youhave 4 teeths you can use a hall sensor.


AF

Hello Arve,

do you have any explanation why a hall sensor can't be used ? Thanks.

Regards,
Chris

Arve is wrong with this comment. A Hall effect sensor can work perfectly fine with a 60 tooth wheel provided the sensor is designed for it. Many OEM's use this combo. Perhaps he was talking about some of the generic Honeywell or cherry industrial sensors which often aren't fast enough?
Your wave form is quite distorted so that gives the suggestion it is not fast enough. What is your sensor - is it oem and matched for the wheel?

Hi

The hall sensor is not fast enough.
Works on lo rmp but not hi.
The easiest fix is change to magnetic sensor. Wire it on 0v and signal.
If you use hall sensor you must increase the distance between the teeth's.
I did run a C20XE on 2 teeth's + synk.

AF

Arve Flaat wrote:Hi

The hall sensor is not fast enough.
Works on lo rmp but not hi.
The easiest fix is change to magnetic sensor. Wire it on 0v and signal.
If you use hall sensor you must increase the distance between the teeth's.
I did run a C20XE on 2 teeth's + synk.

AF

Many engines use a 60-2 wheel and hall sensor.

Arve Flaat wrote:Hi

The easiest fix is change to magnetic sensor. Wire it on 0v and signal.
If you use hall sensor you must increase the distance between the teeth's.
I did run a C20XE on 2 teeth's + synk.

AF

Hi Arve, I still couldn’t fix the problem. Maybe, a magnetic sensor wouldn't have any problems with the 60 teeth wheel. Can you recommend a magnetic sensor?
Teeth distance: 4 mm
Teeth width: 2.5 mm

I want to try it. Thank you in advance.

Chris

Are you using the OEM sensor and trigger wheel ?

No. I use a SICK Hall sensor that should be capable to deal with the 60 teeth up to 6000 rpm because of 8 kHz, but in fact it doesn't

At 1000 rpm everything works fine, the ref signal has a nice square shape (for both! magnetic and hall configuration in motec ecu). At 1700 rpm the nice shape is gone, triangles appear now as ref signal (in case of hall configuration) and in addition this bad signal even isn't stable e.g. the sensor can't recognize single teeth in some cases so the ref signal stays high while 3 to 6 teeth are passing the sensor (happens for both: hall and magnetic config.).

Why can you not use the OEM trigger wheel and sensor then ? Surely that would be easiest and most reliable option ?