computerwi

I've noticed that the NX200t makes quite the racket in the morning on a cold start. For the first 30 seconds, the engine RPMs hover around 1400 rpm and a distinct rattle can be heard. Once the RPMs drop, the engine is pretty quiet and usually drops to less than 1000 rpm (quite low in my experience with Toyota engines). Revving the engine even higher than 1500 rpm doesn't make the same rattle. See the video below.

Note in my video, I've already reproduced this 3 times (to record for you guys) so the engine isn't completely cold anymore. However I can get the 30 second "rattling period" to consistently occur.

I understand it is common for the engine to rev higher when it is cold, but is the rattling normal? Has anyone else experienced this?

Swacer

Yeah, mine will make metal rattle sounds (like heat shields vibrating) when I first start up. Usually when it hits normal idle (20ish seconds later), the car will be quiet.

I've debated getting under neither and looking for a loose heat shield but have been too lazy thus far.

Drtbk4ever

I noticed that the other day too as my wife started her NX while I was in the garage. You should hear it from outside the car. It does sound like something is loose.

Camper01

Mine too has this noise. I have 5000 miles on it but still has the same rattling and noise every time I start, but it will only last for about 15~20seconds.

kchnew

My NX 200t has the same behavior. But I found out it only does this in the morning in the garage or after you park it for some time, maybe a couple of hours, at day time. If you go to grocery store for 5 or 10 minutes, it does not give this rattling sound when you start.

ChazzLexus

Direct Injection

Swacer

Um....you weren't serious....right?

Direct injection will only contribute that you will hear tapping from the fuel injectors, and that's a sound that won't go away.

Swacer

In listening to your video I hear nothing out of the ordinary.

dCota

Same here!

offroad200

I believe it's coming from the PCV valve and is considered normal. With the engine cold, open the hood and remove the engine cover. Have someone start the car. You should notice it a lot more and from what I've seen, it appears to be the PCV. I'm not sure if it has something to do with the turbo and the system getting pressurized or not.

computerwi

If you guys listen closely to the first 30 seconds (might need to crank the volume a bit), you will hear a rattling sound like a loose metal pan. My personal thoughts are that the it's the high RPMs generating a resonant frequency that is causing things to vibrate. But...why doesn't it do that when I apply the throttle then?

ChazzLexus

Hi Swacer

My brother's 2015 Mazda6 GT does the same thing for 10 seconds when starting the car cold just like my NX200t Fsport.
We were told by the Mazda service advisor its fairly common with direct injection engines.

computerwi

As far as I know, Toyota engines usually employ port and direct injection and the 200t is no exception. I'm not expert, but I believe the engine uses port at lower speeds (e.g. idle) and port & direct at high speeds? Can a smarter person advise?

My IS350 does not make similar noises.

cgoing

Did you find a solution to this? My car makes the same noise on start up. for about 50sec.

GoHuskers

No solution since it's normal.

if you have ever owned a Toyota truck engines you will know how LOUD the engine is at start up.