I re-did all my taps into the factory computer. I used a terminal block behind the glove-box to make my connections to the logging harness, and re-wired and soldered all the connections at the computer and heat-shrunk all the wires. I also relocated the ground to a chassis ground rather than tap it from the vechicle's harness. The main 12volt power is still being tapped at the vechile's ECU wiring harness. I also installed a 5am fuse in series at the 12V connection which is then split into the M-500 and the G-sensor.
All other signals logg flawlessly. The speedo signal is still irratic, and gets pulses even when the car is stationary AND when the units in the logger speed calibration are zero.
I did not have a chance to try the input on speed2, but I'm 100% certain that all the taps are solid and secure, the ground has been relocated and has a resistance of 0.4 ohms. I'm trying to work the problem and isolate anything that could cause this issue. I'm now leaning towards that the unit itself maybe malfunctioning from the beginning. Is there anyway that I can test the unit myself to ensure that it is working correctly? Could the 12v power source be causing signal noise? Again, that's for all the support so far.