Hey S2KI Fam, long team lurker... first time poster.

Please help me determine if my engine is producing a rattling sound or if everything sounds as it should.

I feel as if my engine produces a rattling sound (best described like an empty spray can rattle) primary heard the loudest during a cold start. I feel as if the sound remains but tones down once the car is idling.

2001, 113K Miles, Oil Changed less than 500 miles ago. Ballade TCT installed by previous owner around two years ago. Valves adjusted as well around two years ago.

Any feedback will be appreciated!

https://www.youtube.com/shorts/tbAjCz-XwmY

 

These engines have solid valve lifters and are best described as "klicky." I don't hear anything BUT there are experts here who may. Do some searches as I recall the only true way to check this noise is with the hood closed.

Ballade TCT has a poor reputation with claims it tends to over-tighten the chain and damage the engine.

-- Chuck

 

They can have a bit of a ratlesnake sound on cold start, mine went away with the Bilman TCT upgrade. But these cars have lots of rattles, including exhaust heat shields on the underside.

 

Outside of the slight raspy sound, I don't seem to hear anything unusual. Billman has a recommended way of identifying TCT noise with the hood down, 5 feet from the car.

 

I cant view your video but I also have a slight 'empty paint can' sound when warming up, but disappears at temp... it was pretty concerning.

With the car on jack stands and running, I was able to track it down with a mechanic's stethoscope to the oil pan. When upgrading my oil jet bolts, I checked for con-rod play and the axial movement along the crank of the cold rods replicated that sound exactly. The movement was ever so slight, maybe .002-.003" but the clanking noise was distinct.

My theory is that as the engine warms up, the rods and caps expand (general rule of thumb is .001" per 100F for steel, a warmed up engine is ~180-200F) to a point where the fit is perfect with zero play with oil pressure filling the gap. I bet the sound will be more pronounced in sub-zero temperatures but have not really confirmed.

That being said, get that Ballade TCT off and get a Billman but timing chain noise is more like a playing card hitting a bike spoke and much faster than the cold rod noise.

 

If your theory is correct, it should keep rattling until temps rise. The fact it goes away quickly would mean oil pressure has filled those gaps, preventing noise (assuming noise is indeed the gap you discovered, which certainly seems possible).

So I'm saying its not metal expansion making noise go away, its oil pressure.

 

Here is the video for you to review:

 

Sounds good. Definitely no chain noise there.

 

I think its a combination of both... at idle, oil pressure is really low to where the pressure generated is not enough to fill the gap created by the rods not being fully thermally expanded (still ~.002-.003" undersized from nominal at operating temperature) and has some slop causing the knock. When the RPM is sped up, oil pressure goes up and is likely sufficient to fill the gap.

Once the engine and all of the internal components are warmed up, the knocking goes away making me think the idle oil pressure is sufficient to take up the now .001" or so gap between the rod and crank. Another reason why warming up an engine before driving hard is so important. Again, I am talking linear movement along the crank center axis (front of engine to back of engine). I wish I took a video when the pan was out...

OP, that hollow relatively slow but consistent metallic knocking is exactly what I am talking about. Like the expert Billman said, the chain sounds fine. The valvetrain is inherently noisy and not cause for concern. A bad belt tensioner or idler pulley bearing can also cause a racket (and can be pretty easily replaced) but your video sounds like a healthy, COLD, engine.

Billman, curious if you have any insights on my theory? I spent some time looking into this as well awhile back and did not really find any answers. Thanks.