tachometer going crazy and speedometer not working.
 

yea i have a 1997 mazda protege lx 1.5 dohc. I changed the alternator last night and after doing that i went to drive and my speedometer was not working and my tach was jumping all over the place not in sync with engine at all! than this morning i get in and it wont start cuz the battery was dead so i replaced the battery with a brand new one and the problem continues. and now i have a check engine light on that says my new battery is dead but tested it just to make sure and its still good. can anyone help this is a very annoying problem and would like it to be fixed...

sounds like the harness or the ground wire didn't get reconnected correctly.

well everything is hooked up one thing i have noticed is that i cant get the positive wire on battery all the way tight i mean the bolt is all the way tight but its still loose. someone told me to run a new ground from negitive terminal????

that could be it (the positive terminal, that is). it's not recharging the battery because of bad contact. it might make reasonable contact while the motor is off, but makes bad contact when the motor is running. try to bend the terminal in a little while the bolt is loose and the battery is disconnected. see if that makes any difference at all.

well just got done swappin out the possitive terminal and the problem is still there:confused: need help please!!!

well got it fixed it was the positive terminal after all when we put the new one on didnt clamp it down good enough to the wire seen that this mornin thanks for the replys!

well that only worked for not even a day had to jump my car this mornin and now the same problem is back:eek:any help?????