[RoelP]

Hi all,
I'm concerned about a noise in the engine of my 2023 RAV4. This noise occurs after every cold start, regardless of the outside temperature, and disappears after about 15-20 minutes. It seems like the noise is gradually getting louder.

During the 30,000-kilometer service, I mentioned this issue, but since the engine was warm, they couldn't detect the noise. Initially, I thought the noise was coming from the serpentine belt, so I didn't worry too much about it.

Currently, I'm on vacation in Austria (from the Netherlands, 1100km drive) and have removed the serpentine belt to see if I could identify the problem. Unfortunately, the noise is still present, even without the belt and seems to be coming from the timing chain side near the crankshaft pulley. It sounds mechanical and strangely completely disappears after 15-20 min, only to come back after every cold(ish) start. I’ve recorded it without the serpentine belt mounted:

I've already made an appointment with the local Toyota dealer, but I’d really appreciate any input from you guys. It could be the timing chain, but feels a bit unlikely after just 34.000 km’s. I bought the car new and it’s religiously serviced.

Thanks in advance!

 

[Tazio Nuvolari]

Are you using the OEM Denso YZZN1 oil filter or an aftermarket brand? I'm speculating that the oil filter may be defective and is not allowing proper oil flow rate and it may be screwing up the oil actuated exhaust camshaft VVT until the oil reaches a certain temperature after 15-20 minutes when the noise stops. Are the dealers in the Netherlands still using 5w-30? What brand of oil is in the engine now?

 

[RoelP]

The dealer uses Denso filters, it’s not the YZNN1, I will check tomorrow what the part number is on the filter. First service they used TGMO 5W30, second service they used TGMO 0W20. As it’s still under warrantee I don’t want to change anything the dealer uses as I might void the warrantee.

When I first heard the noise, it was on the 5W30 oil. After the service with 0W20 and new filter nothing changed. Over the past few weeks it seems to be getting louder.

 

[Automatic]

Interested to see what happens with the this, I hope the dealer visit goes well.
That location you’re describing sounds like it could possibly be coming from the oil pump which is item 6 in the illustration. Several other things driven or associated with the timing chain as well…

 

[Tazio Nuvolari]

a noise in the engine

Any check engine light (MIL) or other trouble lights? Any MID warnings? Be sure the dealer hooks it up to Techstream and does an OBD2 scan for DTC codes. Don't just let them listen for engine noises.

 

[RoelP]

Interested to see what happens with the this, I hope the dealer visit goes well.
That location you’re describing sounds like it could possibly be coming from the oil pump which is item 6 in the illustration. Several other things driven or associated with the timing chain as well…
View attachment 220167

It sounds like this area indeed. Hope the oil pressure is ok and I’m not slowly killing my engine

 

[RoelP]

Any check engine light (MIL) or other trouble lights? Any MID warnings? Be sure the dealer hooks it up to Techstream and does an OBD2 scan for DTC codes. Don't just let them listen for engine noises.

No warning lights at all, also the engine runs normal. Good idea to ask the dealer specifically to look for any issues with Techstream. Especially concerned about the oil pressure

 

[Tazio Nuvolari]

Especially concerned about the oil pressure

I would not worry excessively about oil pressure. If there was actually a serious issue and the oil PSI was seriously out of range the oil "idiot" trouble light on the MID would light up. There is both an oil pressure and oil level sensor on the 5th gen RAV engine. With regards to the strange noise I would not be surprised the dealer tells you "they all do that." Just be sure they really scan for all DTCs and give you a written print out with their findings.

 

[Tazio Nuvolari]

. Especially concerned about the oil pressure

The ECM is continuously monitoring the oil pressure thru the oil pressure sensor and the ECM is continuously (by the millisecond) adjusting the oil pressure up&down using the oil control valve to regulate the variable oil pump. If there was an oil pressure irregularity or failure you would get probably both an oil light and check engine light and most likely some sort of MID warning notice. Here are some of the warning lights and notices you might get if your oil pressure failed (from my 2021 gas model XLE owners manual):

 

[Turtlepowa]

Don’t worry about oil pressure. Oil filters have a bypass valve for a reason.

sounds like it’s coming from the electronic water pump & thermostat housing area to me. That might explain why it only happens when cold. Maybe once the thermostat opens, noise goes away. Why? Not sure. I’d have to read up on how our cooling systems work and are designed.

 

[Tazio Nuvolari]

Maybe once the thermostat opens, noise goes away. Why? Not sure.

That IS a good idea. Possibly OP has an air bubble somewhere in the cooling system and it needs to be bled.

 

[Automatic]

The frequency of the noise is half of the crank rpm, so something driven from a camshaft maybe?

Isn’t that electric water pump off upon cold starting?

 

[Automatic]

It sounds like this area indeed. Hope the oil pressure is ok and I’m not slowly killing my engine

Thinking you would likely have some very noisy hydraulic lifters if the oil delivery were failing.

 

[Turtlepowa]

Isn’t that electric water pump off upon cold starting?

Good question, I’ll try checking with scan tool sometime

 

[Tazio Nuvolari]

The frequency of the noise is half of the crank rpm, so something driven from a camshaft maybe?

In my post #2 I speculated the issue was in the oil driven VVTi module on the exhaust camshaft. Toyota engines of various designs are notorious for a VVTi rattle on a cold start up after a lot of miles or when they don't get the oil changed enough--and also if the oil filter is defective and BYPASSES dirty, unfiltered oil all the time. Here is a Car Care Nut (Toyota master mechanic) video explaining Toyota VVTi systems and he mentions the 5th gen RAV Dynamic Force engine exhaust cam VVT at 19:36 minutes. He emphasized the issues caused by infrequent oil replacement and dirty oil clogging the mechanism.

 

[RoelP]

Thanks for all of your input so far! At this point both my dealer at home and the dealer here in Austria seem to be taking it seriously. Have to wait for the outcome ofcourse, but so far so good 🤞

Hope to get an update from the dealer later today

 

[Turtlepowa]

Good question, I’ll try checking with scan tool sometime

So it does look like the water pump functions before the thermostat opens @ 185F. It jumps around depending on temperature and rpm. I was going to take pictures and make notes on the pics, but got lazy and just made a (long-ish) video that people can skip through if they’re curious. (I kept recording because I was curious to see when the thermostat opens, and what happened when it did)

 

[Greasy]

Engines make noise.
Does the vehicle have a warranty? If so, don't worry about it.
If the noise is internal the engine, and you only have 30k km, you 'might' have an issue. This depends on oil levels and previous maintenance history. All you have to do is run the oil low once, or skip 1 interval, or use a fake motor oil, or a defective oil filter, and you ruined it.

The 2.0 isn't big enough for a Rav4. So, it'll spend much time at higher RPM's moving that vehicle around. This is a market specific choice. Does this have the 8-speed automatic, or the CVT with low gear?

So, with 30k km, how many oil changes since new? 2? 3? What oil was used each time? BE SPECIFIC.

Was this vehicle purchased new in your location? Or was it imported used, damaged, rebuilt?

My recommendation now would be to run an engine flush, change the oil and filter, use a quality synthetic oil for you weather/location, and a name brand oil filter.

A good flush product:

Engine Flush

Cleaning fluid for clearing the engine interior of troublesome deposits. Brings all types of oil-soluble and oil-insoluble residues into suspension and removes these from the oil circuit during the next oil change. Following this, the engine that has been cleared of deposits and contaminants and...

www.liqui-moly.com

And, something to add to the oil to help with a possible wear issue:

Cera Tec

High-tech ceramic wear protection. Reduces friction and wear through ceramic compounds offering high chemical and thermal resistance. Prevents direct metal-to-metal contact, thus increasing the assembly service life. Reduces fuel consumption in gasoline and diesel engines thanks to the...

www.liqui-moly.com

I am not sure what oil/filter/additive brands are in your country or autopart stores. But, denso/tgmo is nothing special. What other brands of filters are available? motor oils?

 

[Turtlepowa]

Engines make noise.

Honestly I was thinking something similar to this. With my last car, new owners would visit the forum thinking something was wrong with their car. In reality, there was nothing wrong, the injectors were just super noisy and it was a normal noisy engine.

I watched the video again, and honestly, I don’t hear anything abnormal. I wonder if the engine is just more noisy than their last one and they’re not used to it. (Edit: especially since the car drives fine, low mi/km, no codes, etc)

 

[Tazio Nuvolari]

I also thought that at first. Since the camera and microphone was held very close to the engine I suspected the slightly odd sound may have been caused by that. We owners rarely bend over and put our ears right next to different parts of the engine. I give OP the benefit of a doubt and think it is always possible there is a problem with his engine.