what is the vehicle speed sensor instrument panel pulse divisor located for under scalers in the bin for a 7727 ecm, can this be used to adjust the speedometer.
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what is the vehicle speed sensor instrument panel pulse divisor located for under scalers in the bin for a 7727 ecm, can this be used to adjust the speedometer.
Not sure on the scalar but I don't believe the 7747 has a speed pulse output.
this is a 7727, the way i understand it the vss sends an ac signal to the ecm then the ecm converts it to a square wave that then gets sent to the speedometer, cruise control, and then radio, this is on a 90 vette. I am not sure what the vehicle speed sensor instrument panel pulse divisor does but it is set to 0 in the stock tune. I tried googling it but cant seem to find anything that gives a good definition.I am changing my rear gearing from 2.59 to 3.07 and the plastic gear for the vss that i need are hard to come by. I will have to use this http://www.dakotadigital.com/index.c...rod/prd126.htm to correct thespeedometer, I would rather find a correct gear or adjust via the ecm if possible. I did find the gear I need on ebay but their asking $149.00 for a $10.00 gear.Quote:
Originally Posted by lionelhutz
Damn, read that wrong. You have the magnetic sensor plugged into the side the tailshaft driven with gears, right? That setting just changes a divider and can't be used for what you want. The PCM just has a hardware circuit that takes the VSS input and outputs it again. Basically, the sensor produces 4000 pulses per mile and when the scalar is set to 0 the hardware in the PCM outputs 4000ppm and 2000ppm. If you set it to other values you get some other dividers that won't help you.