Sky high voltage

[rsunahar]

I don't understand what's going on.
On my logger, I'm getting 17volts!
Sometimes, it drops to 13v at idle, and my dash lights dim significantly at night.
Also, I can hear the fuel pump screaming (walbro) more than normal.

What could this be?
What should I replace?

 

[rsunahar]

Sorry...i found a thread regarding screwed up voltage regulator.

I hope that's it.
But this means I need a new alternator, and this is my third

 

[RamenPride]

But this means I need a new alternator, and this is my third

I'm already on my third one

 

[Sean485]

Yeap, my 2 week old alternator from advanced auto did that. Halfway through a 3rd gear pull... "d*mn those dash lights are bright..." look over at the afc *16.9 volts*...

It also killed my 3 week old silvania silverstar headlights... At 30 bucks a pair for the lights, I was not pleased :thumbdown

Do you have a warranty on the alternator? Mine had a warranty but they wouldnt cover the headlights :thumbdown god knows what i would have done if it had killed the afc or something with voltage that high

 

[rsunahar]

Yeap, my 2 week old alternator from advanced auto did that. Halfway through a 3rd gear pull... "d*mn those dash lights are bright..." look over at the afc *16.9 volts*...

It also killed my 3 week old silvania silverstar headlights... At 30 bucks a pair for the lights, I was not pleased :thumbdown

Do you have a warranty on the alternator? Mine had a warranty but they wouldnt cover the headlights :thumbdown god knows what i would have done if it had killed the afc or something with voltage that high

Okay, I managed to hook up a multimeter to the car today to verify the logger's voltage.
Yes, the logger is right on.

Here's the weird part:
I decided to begin my test with a voltage check at the battery with the engine off. It read 18volts!!!! STRANGE...

I verified this twice, just in case my multimeter was on the wrong setting.

With the car on and revving at 3000rpm, the logger also reads 18 volts.

Now I don't know whether it's a really really strange battery, or a faulty alternator.

I was under the assumption that a 12volt battery can hold only 12volts. I didn't think it could hold 18volts. That's super strange. What do you guys think?

 

[Sean485]

Get a battery tester with the ability to put a load on the battery, i'd be willing to bet as soon as you put a load on the battery it'll drop back down to its proper voltage and stay there.