Hi, I own a 1990 vn ss & I have an issue with starting. First thing every morning when I fire it up it starts straight away first turn, then when I leave work at the end of the day it has to turn over a several times and sometimes starts & then stalls but if I put my foot on the throttle it helps it but like I said in the morning everyday its starts straight out. It has a 70mm throttle body, could this be a bad map sensor?