Burbling / gurgling noise at 2500-3000rpm, knock, rattle? (Video inside)

[highway7]

Hello

Would like some help as to diagnosing a sound, not sure if I just noticed it now or if it has always been there.

From 2500rpm to 3000 I hear a burbling / gurgling sound from the front of the car, I'm thinking in the engine bay. It is louder when the engine is at operational temp, when cold the sound is very quiet or almost non existent. I hear it mostly in first gear, I can hear it a bit in 2nd and 3rd but at 4th or past I have to really focus and hold the rpm at 2500ish to hear the noise. When accelerating at WOT I don't hear the noise because I go past that RPM range so fast, and AFAIK I don't hear it above 3000 rpm even if I held it. As well, in neutral revving the engine I can hear the noise slightly, but tapping the throttle I do not.

Anyone have an insight? Normal? Rattle of something loose? Rod knock?

Car is a 2013 FRS manufactured in Aug 13, 123 000 km manual trans


[ame]https://m.youtube.com/watch?v=Ve_P5WQOxxg[/ame]

[ame]https://m.youtube.com/watch?v=qeukrXDKVnA[/ame]

Video is with the windows rolled up. If anyone likes I can upload more videos (revving st idle, windows down)

Thanks

[ClownShack]

I have been experiencing this as well in 1st gear. Ever find out what is going on?

[ermax]

I just got a 2013 with 80K miles a few months ago and mine sounds like this in the same RPM band. It stressed me out because to me it sounds like rod knock but in the two months of owning the car it hasn't progressed at all and cold starts sound silky smooth unlike most cars when a rod bearing is on it's way out. I'm sort of just writing it off as a trait of this car. Maybe related to AVCS or direct injection. The other thing that makes me think it is NOT rod knock is that it only does it under light to medium load (at least on my car) where as rod knock is normally louder when there is no load or very very light load. I've destroyed a TON of rod bearings over the past 20 years so I've got a good idea of the warning signs.

Have you owned this car since it was new?

[Tcoat]

Originally Posted by ermax

I just got a 2013 with 80K miles a few months ago and mine sounds like this in the same RPM band. It stressed me out because to me it sounds like rod knock but in the two months of owning the car it hasn't progressed at all and cold starts sound silky smooth unlike most cars when a rod bearing is on it's way out. I'm sort of just writing it off as a trait of this car. Maybe related to AVCS or direct injection. The other thing that makes me think it is NOT rod knock is that it only does it under light to medium load (at least on my car) where as rod knock is normally louder when there is no load or very very light load. I've destroyed a TON of rod bearings over the past 20 years so I've got a good idea of the warning signs.

Have you owned this car since it was new?

Ya boxer engines make noises like nothing else and it takes some getting used to. Took me months to get over the fact that the injectors sound just like a lifter that is ready to self destruct at any second. If my old big block V8s had made most of the noises these things do I would have had them apart in a heartbeat.

[humfrz]

Originally Posted by Tcoat

Ya boxer engines make noises like nothing else and it takes some getting used to. Took me months to get over the fact that the injectors sound just like a lifter that is ready to self destruct at any second. If my old big block V8s had made most of the noises these things do I would have had them apart in a heartbeat.

I concur ....... except back-in-the-day, if I heard those sounds ......I would have just put heavier oil in the engine ......


humfrz

[highway7]

I'm the 2nd owner of this car, have put about 6k km on it since buying it May 2017.

Don't remember hearing the noise when test driving the car. I only notice it now when driving with the windows up due to the winter.

The noise is only present when I accelerate at a certain rate. If i accelerate any slower or faster the noise doesn't exist. Especially in 2nd gear+, if I accelerate quickly I don't hear a thing. And when I am cruising on the highway at 3k rpm (around the same rev range where I will hear the noise in 1st gear) in 6th the noise doesn't exist at all.

A few weeks ago, the temp was fairly warm 12C and the noise was significantly quieter. I'm thinking this noise is due to temp. Going to wait until warmer weather to see if this noise still exists. For now just trying to enjoy the car.

No knock or anything at cold start and I've left it outside in sub 0 temps. No knock at idle once warmed up. Have taken her to redline multiple times since this noise and it hasn't got any louder. Csr still pulls the same.

[ermax]

Sounds exactly like my symptoms. Although you don’t hear it in 6th I suspect the sound is there with moderate load you just can’t hear it over the road noise.

A friend of mine runs a monthly car show in my city which turns out as many as 700 cars. I have seen large numbers of FRS owners there but I haven’t been able to make it to a show since owning my own FRS. I’ve been wanting to get out there to talk to some of the other guys and go for a ride in a few of them or take someone on a ride in my car just to rest my mind. As I said mine hasn’t progressed at all so I’m kind of over it at this point but still wouldn’t mind hearing some others just to be sure.

[BRZnut]

I'm just the opposite from the OP, mine will sound similar (but not as loud) when the engine is cold but the sound goes away once it is warmed up. Does not sound like rod knock to me

[ermax]

In my case I should clarify that it doesn’t seem temperature dependent. It just sounds rod knocky around 3000-4500 when under light to moderate load in all gears and all temps. Cold starts on this car are the smoothest/quietest of any of my other cars.

[Butterballz]

Mine makes the same sound at those rpm ranges. I assumed it was a rumble from the headers since I believe the stock headers are still slightly unequal in length. But if it is not, then please let me know cause I don't want my engine to go boom.

[strat61caster]

1st video dead
2nd video sounds pretty normal, maybe something a bit loose causing a light rattling noise like the bumper sagging or a bottom cover not fully secured. It could also be totally normal and everything is fine. That light 'rumbling' could very well be the noise the engine makes at part throttle under those conditions, it doesn't sound 'wrong' to my ear.

Ask in the local section for a good shop, take it in for an inspection to make sure everything is buttoned up, someone who knows these cars should be able to spot a missing fastener or something out of place pretty quick. Should be <$100 which may be well worth it vs. the time you'll spend pulling your hair out if you don't know what you're looking for. If they say it's good, trust them and accept that you bought a noisy cheap sports car.

[Ultramaroon]

I hear it.

1. Is your oil at anything less than full?

2. How many miles on the oil? filter?


Amsoil sooper dooper or Mobil 1, doesn't matter. I can't seem to get more than 4500 miles out of a change before I get really uncomfortable with the sound.

Mind you, I might be stretching the comparison but I hear what I hear.

[mazeroni]

Sounds 100% normal to me.

Maybe a little more rumble-y and less gravely than my car, but that might be the position of the mic.

I never drive without music playing because I get very insecure about the car's noises.

Gotta crank some speed metal and just hope for the best.

[highway7]

Originally Posted by Ultramaroon

I hear it.

1. Is your oil at anything less than full?

2. How many miles on the oil? filter?


Amsoil sooper dooper or Mobil 1, doesn't matter. I can't seem to get more than 4500 miles out of a change before I get really uncomfortable with the sound.

Mind you, I might be stretching the comparison but I hear what I hear.

Oil is just slightly below the max dot on the dip stick. Check my oil every 2 weeks or so, has never dropped near the low dot.

Just changed the oil and filter 2000 km ago (Used Toyota OEM filter and Toyota 0W20). I heard the noise even before the oil change. Nothing out of the ordinary with doing the oil change, drained out 5.2L or so and poured in 5.4L as per manual specs, the 5.4L brought it to exactly halfway between the MAX and MIN dot. I poured in an extra 300ml or so to bring it just below the MAX dot.

Car has been serviced at Toyota it's whole life, the KM were higher than what I wanted but it was a good deal and had all service paperwork with it, oil was changed every 5-8k km.

Thanks everyone for the input. I'm just gonna drive the car, if it's normal then it's normal, if something breaks then I will know then. No point having anxiety over it, it's just a car.

Cheers all