What's wrong with my truck? [Resolved]

Hey all,

For about 4 days my truck has been doing this on a cold engine start:

https://youtu.be/LHis-SM1-Ak

I observed the voltage just after I ended that clip, and it climbed to 14.9V - higher than I've ever seen on it.

About 10 mins later after a stop for a drink, I took this:

https://www.youtube.com/watch?v=-xS-Newimhw

You can hear a faint "sshhhooook" in the video when the engine starts, but it is quite loud IRL. This noise occurs on ever warm/hot start now. It sounds to me like a vacuum leak or a belt, but idk. (Belts are probably due for a change though) Voltage is kinda in the normal range here. It usually reads 13.2-13.7 for normal, 13.8-14.7 for charging, but higher than 14.2 is rare.

Let me see what you guys think before I make guesses.
Battery was tested at AutoZone yesterday and is only 6 months old (it replaced one that only lasted a year).
Other info:
I have a moan/whine at idle like something is rotating unbalanced.
A friend jumped my battery backwards a few months ago right before I got it replaced.
Visible belts aren't frayed, visible hoses aren't cracked.

Do our trucks have voltage regulators that go bad?

 

Subbed because my truck occasionally starts up the same way when cold. Only every so often though, and one time it wouldn't start at all...only cranked and cranked until I feathered the gas and it barely got going. Hasn't done that since though. But I'm curious what it might be.

Did you get the alternator tested at Autozone too? I took my truck over there after my issue and they tested both and said they were fine.

 

Besides taking to long to crank I'm guessing I'm missing the problem on your cold start.

Voltage, around 12.5v with the engine off is normal, a voltage drop during cranking is normal, 13.5 to 14.7 running, normal.

 

Ya that second clip is a successful start, but it makes an unnatural noise. I'll try to get a clip of the voltage reading on a cold start too.

 

I did not. I asked them if my starter was fine once and they said yes. In my head I was like 'just because I made it here, doesn't mean my starter is fine...". I didn't believe them, and one week later I had a new starter installed and my car was fixed. The point I'm trying to make is that I'm not very inclined to have them test much more than a battery. How would they go about testing the alternator anyway?

 

I'm not exactly sure how, only that they can...here's a link; http://www.autozone.com/landing/page.jsp?name=starting-and-charging-guide-alternator

Interesting it says they don't provide that service in CA but the one near me has done it before no questions asked.

 

Here is a clip of the voltage on a cold start. This time I left the key in the on position for a few seconds before I turned to ignition, which seemed help a little bit.

https://youtu.be/id1-Kqcdx3w

I'm ready to rule out electrical issues since it's clear the voltage stays relatively high, even during the start. A dead or dying Alternator would leave the battery in a discharged state, and if anything it seems like it's overcharged.
What's next? Fuel pump? Injectors?
I put two doses of injector cleaner into the gas a couple weeks ago. I could do a seafoam?

 

I had a wining alternator in a vehicle once. Very annoying. You could rule that out by taking off the alternator belt before a cold start.

The voltage regulator is built into the alternator IIRC.

 

Just a small update.

Turning the key to "ACC" for 3 seconds or so and back 3 times essentially fixes all issues. That combined with the sound I hear when starting (which I now realize kind of sounds like an engine cough as it runs out of gas) has prompted me to order a new fuel pump.
URDs Walbro 255 since I have been considering a turbo build for some time. URD because I can't find any cheaper place that looks authentic.

 

For archival purposes, and because I hate finding threads that were never resolved:

The starting issue got progressively worse until around February when I finally decided to take out the starter. (This was after upgrading the fuel pump.) The top of the gear that connects to the crank had sheared off to a 45 degree taper, so when it would rotate, there was no grab, so it continued to shear each false start until it finally managed enough friction to spring out far enough for the crank to grab it.
Free replacement from AutoZone warranty, though I was really reluctant to go with their shitty remanufactured part again.
That solved the starting issue.

There was a voltage regulator violation during a battery check (+- 0.05v or something... which was apparently out out spec), and that drove me to do the swap. I've also done the GM alternator swap and my accessory belts since then.
That solved the whine.
I have my original alternator if anyone wants to buy it (on the off chance they're an OEM nazi they'd like to refurb the regulator & brushes), otherwise I'll just keep it in my stash haha.

Thanks