are you supposed to be able to see crank sensor reading in a high end scan tool for a B20 ? what should the reading be during cranking? id just like to verify the suspicion its the sensor before tearing off the belt cover

 

The TDC the ecu looks at for starting is in the distributor.

The crank sensor by the crank is the crankshaft fluctuation sensor. Mostly for emissions to my knowledge, and doesn't keep from starting.

Idk about on a scan tool. Oscilloscope on the sensor is probably the way.

Hope that helps.

 

so basically my distributor crank sensor can be messed up and i'd still get spark at the plugs ?

 

No.

Basically the crank fluctiation sensor at the crank can be messed up but you should still get spark if the distributor TDC is working correctly.

TDC is top dead center. There is a sensor in the distributor for this, and the ECU reads it only durring cranking to know when to fire spark.