So I just recently purchased a '16 Trail Edition Premium after debating back and forth for a while and lurking the 3rd gen thread at Tacomaworld and the 5th gen thread here. Super happy with my purchase, and this forum really helped with a lot of research and helped me be confident in my decision. First new car for me ever, and no regrets, so that's a good feeling.

So I just had a few things I wanted to ask about and get an opinion on for anybody that has a minute to respond.

1) There's a pretty "impressive" sound that occurs before I turn over the engine , mainly for cold starts (often don't hear it if it's warm). This noise will normally occur and run its course while I'm letting the 4 or 5 "dings" to occur before turning it over. It also makes a similar sound when I turn the engine off but doesn't last as long. I don't think it's the evap leakage check that occurs about ~5 hours after shutting off that's described in the manual, but I could be wrong. I always hear it before starting and shutting off. Hope it makes sense what I'm saying. It sounds like this:
https://www.youtube.com/watch?v=FyZZMvAry4A
It does not sound like the videos I've seen of the constant humming of the 5 hr later evap leakage check. Anybody have any insight?

2) There have a been a few times where I hit a set of rumble strips before a stop sign (the kind where there are 5 sets of 5 raised paint stripes close together to warn you of the upcoming stop) and I literally hear what sounds like a bell going off from the suspension right after I hit each set of strips. A definite metal pinging sound. Haven't heard it every time, but it has definitely repeated itself a few times now. I do have KDSS. Could not find any threads on this one.

3) I've read up on the 10 miles per month exercising of the 4wd, which I will likely need to do on dry pavement here and there. I have a nice straight stretch on my way to work with a 45 mph speed limit in between 2 stop signs that is about 2 miles long. Does this sound like a good candidate to run 4wd about 5 times a month when I can't get off-road?

4) There was a trailer brake controller pigtail in my glovebox with my manual? Sorry, dumb question, but what is this for? When would I need to install/use this?

Thanks a ton!

2. Is probably these c-clips on the UCAs. They should be tight but aren't.

Not an uncommon thing, but not too common either.

Mine are loose. Dealer has replacements, I just haven't gone in yet to get em put on.

I can take a picture if you need me to.

#1 is more than likely the fuel system charging on start up and draining on shut down. I'm told it has something to do with the ignition interlock/anti-theft. I know that's it's normal for sure though, every toyota I've driven in the last 5 years has had the same noise.

Thought #1 was the brakes. Could be fuel. When i press my brakes it sounds kind of similar. But yeah thats a normal sound.

#2 sounds like same issue I had. It was the c-clips on the upper ball joints. Dealer had to
Actually replace the entire upper control arm assembly. Didn't realize how much it annoyed me until it was gone.

Quit worrying. That noise is the air pump that is part of your emissions system.

Exercise the 4WD every now and then. It does not have to be exactly 10 miles. It does not all have to happen at th same time. If you miss you don't have to make it up. It's not medicine.

Enjoy your vehicle. It's fine.

Thanks for the tip on the c-clips. I'll check for any looseness. No need for a pic, thanks though. I now remember reading about that awhile back, but hadn't made the connection.

Agreed on the worrying. A little hard not to with a new vehicle, but certainly hasn't affected my enjoyment. But mainly I've never had a vehicle with any kind of warranty, so I think more than worrying I'm just paranoid that I'll miss something that should get fixed and/or waste the dealer's time.


Thanks for the replies!