Tachometer Question

greenscobie86 · Nov 12, 2009

Hey guys,

So my new Cobra had shown its first little niggle the other day.

A few times my Tach would become erratic or die all together... Then it would work great for hours. Also the battery light would blink.
I've noticed that it kinda does it when its cold more.

I realize this might sound like my alternator is going out, but I've checked the charging system and its producing 14.3v so thats good.

Could it be a loose connection at the alternator/wiring, or is it at the cluster?

Car has 89k miles BTW...

Any help is appreciated. :wave:

duff daddy · Nov 12, 2009

For the alternator check it when its happening, if possible. It could be failing internally, just not failed yet. Or you could have poor connections at the alternator, or even excessive belt slippage. Try to see if there is a period of time when this happens ie under load (going up hill or accelerating) or if its sporadic.

As far as your tach, you may have a poor pick up, im not 100% on the tach's for the cobras if they are different then the 2v's so you may want to wait for someone more experienced on a 4v car.

greenscobie86 · Nov 13, 2009

Cool Thanks for the input Duffy.

I was thinking it was belt slippage, but thats not it...

I'm gonna go over the entire charging system connection by connection by connection.

Time to break out the Chilton...

greenscobie86 · Dec 2, 2009

Just an update for everyone:

I belive the problem to be a faulty voltage regualtor. Looks like this one is on its way out, however the alternator works mint... Produces 14.31v(no load) and 14.18v(full load)

I'll probably just replace the alternator, since voltage regualtors are really expensive by themselves.

As a side question: Does a voltage regulator out of 2v mod motor fit onto the Cobra/Bullitt style alternator? Just curious...