So my tachometer is acting ...unsatisfactorily. It reads pretty much whatever it wants to, and doesn't care at all what the engine is doing. In the video you can see what it does, but there is also a whine that follows the engine. You can hear the difference between the whine and the engine when I rev it.

http://www.youtube.com/watch?v=fzRQEXmLWM8

I've read a few post that just say to replace the tach, but I don't want to spend money on it, if that isn't the problem. So, thoughts on the tach, or the whining? Bad ground, bad connection somewhere? Where does the ecu draw the signal for the tach from? CPS? I've read through the FSM and the only troubleshooting is from the ecu to the tach.

 

Are you serious? Crap, I know the D21/WD21 Hardbody Pickup and Pathfinders ('94-'97) have had problems with their electronic speedos and tachometers acting crazy. I had to swap my tach on my '95 pickup.

 

Of course I am not serious, I just posted this because I thought it would be funny to hear about random cars that have had tach problems

 

Looks like your Alternator is going since in the video when you had the lights it got brighter as you reved check the charge going to the battery, also check you grounds, as far as the Tach goes i would just pickup 95-97 cluster and swap it over to check. Although I'm not sure but the issue with the Alternator might be related

 

Definitely your tach needs replacing. Also, the alternator is making that whining sound. I t still charges good but if you want that noise yo go away, you have to replace the alternator or rebuild it yourself.

 

Yea, it's looking like it's on it's way out. I put a multimeter the the battery 12.4v, cranked it up and it only topped at 13.8v, which is the bottom of the functioning scale, and under load of lights and heater it dropped to 13.4 and stayed there.

 

i have the same problem with my tach.did you fix your tach can pls share it with me?thanks

 

my tach worked for the first 3 days i had my max it would idle normal range if i hammerd on the gas it would stop at 3k lol still havent fixed it now it stays at 0 idk ..