Okay, after living in my S2000 for two whole weeks, all day long, I've gotten to know it quite a bit better. There's a sound that it makes from somewhere forward of the steering wheel when the engine is between 2500 and 3000 rpms and the throttle is at a position that just barely causes acceleration. I was thinking that it sounds like a stepper motor, or maybe a small multi-bladed fan with air being blown onto it. Then I decided that maybe it sounded like engine detonation. It's not real loud, but once I noticed it, I could detect it any time the stereo wasn't on loud.

The sound goes away almost exactly as the engine passes 3000 rpms and doesn't begin until just before 2500 rpms. If you hold the throttle so that the car is neither accelerating nor decelerating on flat ground, it doesn't make the noise. If you give it just a tiny bit more throttle, you hear it, but much more throttle at all and it goes away. I haven't detected any other conditions where a similar sound is heard.

It does it at all altitudes from sea level to 10,000 feet and with all of the different kinds of premium gasoline that I put in the car. It's my guess that the engine control is mapped to have a little more advanced timing under those conditions than might be optimal.

I'm guessing that this has been discussed before, but I don't remember seeing the discussion. I'm fairly certain that all S2000's do it and I expect it to be a normal part of operation for the car.

Could someone in the know please tell me what the sound is?

Thanks.
----------------------
Trip reports (so far) at:

http://www.geocities.com/srnelson_s2000/Day01.html
http://www.geocities.com/srnelson_s2000/Day02.html

S2000 on Washington Beach


[Edited by scottrnelson on 05-22-2001 at 09:52 AM]

 

Don't know about the sound, but have you ever been to Union Jacks? How about Happs? Ohhhhh, Amelias what a great deli!!! Plesanton is a great place!

 

You may have a bad batch of gas. If you can find anything with a higher octane rating give it a try but at least change locations.

 

I think there is not way what you are describing is detonation. Detonations usually occur when the engine is under load. Probably something a bit loose in resonance at the particular frequency.

 

I distinctly heard pining under mild load, while going slight uphill at 2-5k rpm. I was surprised, but it immediately went away when I switched petrol stations. Use up your current tank, and then switch. See if that does it.

 

Okay, maybe the sound is not so common.

This occurred over 22 tanks of gas purchased at a different gas station each time, hundreds of miles apart. Always the highest octane available, usually 92, but as low as 87 at one high altitude station.

Maybe it's not detonation, but I'm curious as to what the sound is. I would appreciate it if a few other S2000 owners could check to see if they get a similar sound under the same conditions.

Thanks.

S2000 in Joshua Tree National Park

 

Did you check your oil level?

 

i get a small sound similar to that, almost a slight pinging. doesn't sound bad, doesn't get worse over time. Witnesses have said it's nothing, i'm not too worried.