Question Why My MacBook Pro Late 2013 is lagging significantly whenever I plug it in for charging?

[Tyler Cleggory]

I have a MacBook Pro late 2013 15inch that I bought exactly a year ago. Lately it have been lagging A LOT whenever I plug it into the power adapter to charge it. Everything lags and becomes extremely slow when its plugged in (UI, gaming fps)

I've looked online for a solution for a while now and I can't seem to find anyone who's facing the exact same problem as I am, so I hope that someone out here can help me find a solution because this is my one and only PC that I own and its my only goto device for anything that I wanna do ):

I installed an app to monitor my MacBook temperature and its always at 40-55 Celsius while I'm casually using it (watching youtube, surfing the web) as a matter of fact its at 46C right now as I'm writing this and I only have Chrome and Skype open, I'm guessing that's a little bit high for just these two simple apps running?

Also on my activity monitor i've noticed that my kernel_task CPU usage is at 2% when it's unplugged, but whenever I plug it in it rises to 600%!! and then the lag starts..

I tried resetting SMC and PRAM with no results, I installed windows 7 through bootcamp hoping that the issue might be software related but nothing changed in windows either, so what is it?

Nothing have happened to my MacBook prior to this problem that might have caused it, I just woke up one day and my MacBook started acting slow whenever its plugged in for no reason, my trackpad stopped clicking in all the way down as well, don't know if that might be any useful information?

So what could the problem be and what should I do? and please don't suggest that I take it to an apple store or genius bar because those don't exist in my country :/

thanks in advance.

MacBook Pro with Retina display, OS X Yosemite (10.10.1), MacBook Pro Late 2013 15inch

 

[jsmithepa]

This would be a classic symptom of power starvation, but am not guaranteeing you that this is your problem. If so, somehow your AC power is not giving the machine enough juice. No juice, slows down.

Are you using the EXACT SAME AC plug when it was working?
Inspect MacSafe connector, any dark spot? dirt? CLEAN IT.

Download some sort of system monitor app (I know lots of Windows but not OSX) which will display to you all the voltages, frequency and temperature. For example, if 5V is measuring 4.7, then I was right. If the CPU is throttled down from what you expect it to be, that too confirms my suspicion.

 

[mikimm]

I changed my battries and right after that i started having the same problems. when I connect the electric plug the computer becomes very very very slow until it stops responding. when I take the plug out it starts working again.
considered going back to lab to change the batteries again

 

[McHenryB]

Some suggestions here:

http://apple.stackexchange.com/questions/72498/kernel-task-consumes-500-cpu-on-ac-power-sometimes

 

[MrTuRtLe03]

Reset the SMC and PRAM. To reset the SMC, close out of all applications/programs. Make sure the Macbook is plugged in, then HOLD down Command+Option+Shift keys. While holding those, press the power button. The laptop should immediatly power off, and you might here a click. Also, your charging light should go from orange to green. About 5-10 seconds later it will turn orange again. Then, press the power button and HOLD down Command+Option+P+R, you should hear it chime, then turn off. When the screen goes black let off on those keys. You should see the screen is brighter, and the next chime is louder.

If that doesn't solve it the open up resource monitor and see if anything is abnormal.

 

[juliaojoa]

I have se same problem. I have a MacBook Pro 15''2017, already Reset the SMC and PRAM, anyone have any new idea? https://www.youtube.com/watch?v=Q-6R9-VmDvg&t=51s