The Nissan Path

So I've noticed a noise I get lately and wondering if anyone has dealt with it before. I'm only hearing it under load, usually somewhere between 2,200-2,500 rpms. Sounds like a heat shield or something similar rattling/jingling around but I can't get it to make the noise at any other time unless it's in-gear and accelerating. It's very obvious in the cabin and you might think it was an internal engine noise, like it gets really raspy for a second or so. It never makes the sound at any rev while in park. I've smacked around the heat shields as well and no noise from them either. Any ideas?

Skinny2 is it only when cold? I have something similar but only when cold frankly I ignore it and it goes away when warm.

You mean engine cold or temp cold? It doesn't seem to matter about engine temp, but you've got me thinking about the outdoor temp. It was doing it this morning (~low 30's F) but only lightly this evening (high 40's).

You know I was going to say engine temp but now you got me thinking mine has only started when the temps started getting say below 30F ?? I wonder if we have the same issue?

Sorry Skinny2 I'm not much of a help!

a lot of exhaust system noises are more pronounced when cold, before the component parts heat up & expand

So I was able to replicate it more this morning. Only seems to be noticeable in 1st or 2nd gear and pretty much turns on right at 2,200 rpm. I can hold it there and have the noise remain constant. Engine was fully warmed up and outside temp was 34F. It really sounds more like a buzz in the exhaust/maniford or somewhere under the hood.

That reminded me of something I read awhile back. There is a TSB for the "power valve actuator" NTB05-015b on earlier models and that almost seems like the exact problem. I'm not sure why it only kicks in at lower speeds and not at idle though...that part seems different than the TSB.

skinny2 wrote:So I was able to replicate it more this morning. Only seems to be noticeable in 1st or 2nd gear and pretty much turns on right at 2,200 rpm. I can hold it there and have the noise remain constant. Engine was fully warmed up and outside temp was 34F. It really sounds more like a buzz in the exhaust/maniford or somewhere under the hood.

That reminded me of something I read awhile back. There is a TSB for the "power valve actuator" NTB05-015b on earlier models and that almost seems like the exact problem. I'm not sure why it only kicks in at lower speeds and not at idle though...that part seems different than the TSB.

the TSB mentions that the rattle occurs @ "around 2,200 RPM"
that's where you mention that yours makes the noise
it's certainly possible that even though you have a later model, the problem could be related
is yours a VQ40?

Yes it's a V6. Maybe SMJ will chime in and have some experience with these. I'm not sure if the actuator is active while in park or not. The TSB isn't clear on that point and I don't get any noise while revving in park.

I did some more testing last night and it does do it when revving in park. It's just very very light and you really can't hear it easily. For some reason it's very loud while under load.

So I'm pretty sure that's the problem. What I've researched sounds like it's not really an issue beyond the noise. I'd rather not perform the TSB but replace the part if possible. Doesn't look like you can just buy the power valve actuator by itself.