VW 4 cylinder engine with distributor.
Hall Effect sensor with 4 window wheel in distributor used for triggering.
Distributor used for ignition, Stepper A to single Ignitior/Coil.
The issue is: RPM value drops very low every few seconds. Does it also misfire / bog than ? Or apparently runs fine ?
- It misfires at those moments
Tried using 5volt and 12volt supply for the Hall Sensor, same results.
Experiment
- pull down HALL sensor input to GND with a known (eg. 1kOhm) resistor and measure DC voltage
- than calculate the measured internal pullup resistor value (depends on order options and order comment but normally around 2k7)
- We've seen a Crysler HALL sensor where 2k pullup (during initial measurements of the engine tried to pull the signal up with a hack: the TPS sensor) was too low to trigger reliably (but 2k7 was OK).
- Maybe this requires higher 4k7 or 10k internal pullup ? Would be nice to measure with scope when the problem shows up.
- The car is far away from my location. I will get to see it in a week or so. My scope is broken so diagnosis will be difficult.
- Tried setting the trigger teeth to "4" (incorrect) instead of "2" and the car started/idled, but dies when the throttle is hit.
- Why would 4 teeth setting run better? (Distributor with 4 windows, turns half speed so one engine rev = 2 trigger edges, not 4.)
Vemslog:
http://www.vems.hu/files/KevinBlack/CSP%20Corrado%20New.vemslog