OK so a couple days ago I had something happen I've never seen before I was driving along listening to music when all of a sudden my truck nearly stalled.

I came to a turned off my radio and began to listen for problems low and behold everything was fine I started off smooth as glass got to rolling and decided to turn my music back up and there was the misfire again.

I thought well that's strange that it happenehappened as I turned the radio on and shure enough I turn the volume down runs fine,turn it back up and I get a miss right after every drum kick.

So has anyone got any idea of what could be causing that ive checked my battery alternator I've got 14.1 volts while charging which seems a bit hight but other than that all seems good.

Weirdest thing is I've had the sound system in for months and it just started missing.

Anybody with any suggestions?

 

Welcome to the forum

There would be no direct connection between the engine and radio

Test battery voltage with key on engine off, with radio on but at 0 or low volume and then high volume, should be no change in voltage, if it drops then radio has a bad power supply

 

would this still apply to an aftermarket radio?

 

Do you have a twenty quadrillion-watt aftermarket system that would suck up so much current there's not enough left for the truck?

 

it's 1000w but I've had it in for months and I just started having problems

 

Maybe your battery was juuuuust good enough to not cause an issue, but now you're really drawing current the battery has degraded to where it can no longer supply the current.

 

maybe but im still only dropping .3v under full load so I'm still getting 13 8v while running

 

OK so I've just went back and double checked my voltage and I'm getting almost 15v charging 14.6~14.8 I'm starting to thing maybe a voltage regulator issue

What do you guys think

 

But is that with your radio cranked up?

 

yea that's with it at full volume

 

If that was just after startup then up to 14.9v is OK

The voltage regulators work based on Electro-motive force, think of its as "Push back" in any electrical circuit

i.e. if you have a 12v light bulb that draws 1 amp(yes a big bulb, lol)
And a 100amp battery, when you turn the light bulb on it only draws 1 amp and then "pushes back" so just the 1 amp flows thru it

So all electrical circuits have "push back", the maximum amps they can use
When you start an engine the battery loses quite a few amps , so less "push back" then when its fully charged, and as a battery gets older it also has less push back, just FYI

After running a few minutes the battery will get recharged and voltage regulator will reduce amp output(which we see as lower voltage)
Generally speaking vehicle voltage with engine running, after 10min, should be 13.8v to 14.2volts
Never lower than 13.5v or higher than 14.9volts

If engine is idling and you have say 13.9v, then turn on all the lights and blower/fan to HIGH, you should see a momentary drop in voltage as AMP demand increased then a return to previous voltage as voltage regulator responded to the drop in "push back" so increased amp output to match

 

Ik so I've been messing with this problem again today I figured I would go to basics to see if I could identify a problem.
started with plugs ,wires ,coils all looked good even when misfire present

checked fuel pressure and same thing.
then silly me figured why don't I check for codes and it turns out I have a p0340 as well as the p1401.

so I guess my question is would this be causing my issue with the radio or is that just a coincidence.