Fuel pump running with truck off

Yep - post#2 in thread

 

I thought it might be the fuel pump of course when I heard it. I decided to look it up and saw all the threads on it this morning. After that I feel it must be normal. Still strange I think that it does this. At least I know it is no different then what others have posted here.

 

Its a test of the EVAP system on the truck. A small pump pressurizes the gas tank and then keeps an eye on the pressure over a period of time, if it leaks too much it considers that there is a hole in the evap system and will throw a code.

 

It's Oh My God 0430 hrs. in the Morning And yep 10 hours after truck was parked and noise coming from gas tank and I have Audio

 

normal

 

Yep... it is normal folks. I first noticed it a couple of months after purchasing my truck. I was on a multi-day elk hunt in the middle of nowhere. It freaked me out pretty good. Got home and researched it... evap self test... done by design.

 

So I am a new Tacoma owner having just purchased a '14. I am not sure if this is the same thing that you guys are talking about and if it is then I apologize for being dense. What happens in my truck is right after the truck is turned off there is a strange noise that almost sounds like the starter o something spinning. It is only for a second or two so it's pretty brief it just sounds strange. Never had a vehicle that did this before so I'm concerned.

 

2012+ v6 trucks saw the introduction of an air injection pump (for emissions reasons - pumps fresh air into the exhaust to help the cats do their job on startup). On the 2013+ trucks the programming of this air injection pump changed a bit to include a shutdown purge (to rid the valves and pump of any moisture buildup from the motor running). This is the sound you are referring to @Hemmer

 

Phew! Thank you!

 

Wife comes up to me a few minutes ago, "there's something that sounds like a motor running in the garage." So I investigate. I do love TacomaWorld... A quick google search led me back to here and viola, I can go to bed now having learned something new!

 

That's why I love this forum so much, I learn something new about my new truck everyday!

 

I can confirm that this happens on the 2018 as well. Page 8 of the owners manual describes the noise.

 

... add a 2019 to the list. My wife comes over and tells me that while in the garage, she heard someone pressure washing or mowing outside. Except there was heavy rain and thunder outside. I went to take a look and there's the noise coming from underneed the truck.

 

Darn, @BajaBornTaco beat me to it. Someone has been bumping this thread every year since 2011, so I thought did get to do an early 2019 bump. Guess not

But I did find this via google after noticing this sound on my wife’s 2016 4runner a couple different evenings. Glad to hear it’s totally normal.

 

New 19 Taco owner just laying underneath admiring Toyota's rainbow of paint markers from QC when this humming/buzzing sound started for no reason. Fuel pump priming or something I thought.. Jumped on TacomaWorld and got informed it's completely normal.. Fuel system leak check.. NICE!!

 

Wow! You guys are the best! Same thing here, we were freaking out, wondering what to do! I searched online, and found this! Thanks so much for the help!

 

Thank the lord for this form. Typed into google this problem. First thing that pops up this thread. God damn do I love us/y’all. Btw sorry to revive this thread.

 

Good thread, had the same thing. Assumed the truck was stuck in the priming cycle.