b20vtec in 90 ef sedan got four codes pending and weird things happing with headlights on my four codes are Iavc tps Iat and Vss which i dont need gots cable tranny recently had blew a fuse on ecu because of four wire oxygen sensor being hooked up wrong fixed that problem now have this new problem which is was driving home one night and my headlights started dimming like i had a bad alternatetor which is not the case but my engine check light came on now i have those four codes also my stock tach jumps at high rpms but its a new dizzy people are saying grounds but ive checked all except the ones under the dash i dont know iam at a lost. what do you guys think thanks in advance