quesswhatidrive

right now in the process of my auto-many conversion i have the park neutral switch from the auto trans ripped out and connected to the wiring harness for the trans. this is so my car will start[&:] . this is due to the PCM difference from auto to many. i also dont have back-up lights b/c of the wiring harness diff. now also my speedometer currently reads about double of what it is supposed to (e.g im going 35 it reads 70ish) the question here is, once i get my PCM reflashed will the speedo read corretly, me and my friend beleive so but we are not so sure, im going to get the correct wiring harness asap so stupid ppl dont drive into me when im backing up, will the two of those for sure get my speedo right?