RPM input from Audi S2 engine speed sensor

[ranz]

I've read many other topics and the WIKI but still I don't get what I have to do, to make it work right. Signal comes from audi S2 3B engine original engine speed sensor, but when I connect it, firstly it showed something like 15000RPM @ idle. I tride to play with settings and got it down under 1000RPM but the gauge jumps up and down showing 200 to 1300RPM range and doe's not stop @ any value. What I am doing wrong? What needs to be done to make it work right?

[billman]

this is for an RS2 and the RPM works well. Maybe you you should see the settings. AFAIK they have the same sensors.

http://www.vems.hu/files/mallon%20kalo.msq

[[email protected]]

Have you got the RPM wired as per the guide suggestion?
http://www.vems.co.uk/VEMSWB/UserGuide/README.html
You may need to try a few different resistor values or get a trimming potentiometer to adjust the reference voltage on pin11

[ranz]

Yes, the RPM input is connected like showed in manual. I measured the signal with ossiloscope from RPM sensor plug and from the VEMS connection plug, the signal is fine, not jumpy or anything. Just now i connected potentiometer and tried to play with it, nothing :( it's still jumping.

[Regler]

Hello

is the audi running?

and have you the vems ecu or other?

[ranz]

I have stock ecu, only vems WB.

[ranz]

Now i connected it to the wire from ECU to RPM gauge and it's working fine (setting 5 and 229) :) only sometimes it shows funny numbers, @ ~800RPM shows for a second something like 300RPM, but not very often.