Hey guy's I've done numerous search's on this topic and haven't found a definitive answer that everyone can agree on regarding the 1800-2000 RPM engine rattle that only happens under load. The heat shield theory Isn't the answer I'm looking for it's not that type of sound. if it was a timing chain then why doesn’t it make the sound all the time if indeed the tensioner is not doing it's job. The engine is fine and feels strong, has power.. just that awful noise at low RPM which sounds Horrendous and gets much worse on a hot day. So for anyone who has a legit solution on this topic please share.

 

Check your engine mounts.

 

its the tensioner idler pulley, and some mechanics can have the magic touch to fix it, or time to care to fix it. have had the noise on mine for 7 years.

 

Its this. Mine did it for a few years and then fixed itself somehow.

 

same thing but i have a new pulley im gonna put on myseld its not hard to do if its not that or my alty then its more than likely something with the wheels hell ya never know lol

 

it would be nice to know how you fixed it ! because techinally by the book the idler pulley has no adjustment capability on paper.

 

I kept driving it for year and lived with the noise until it stopped making the noise. That was how it was fixed.

 

I do have a bad Passenger side mount would this really cause the rattling?

 

Rattling as in detonating? What grade octane are you running?

 

to clarify and not confuse anyone , the tensioner idle pulley rattling is specifically around 1600-2100 RPM at medium controlled throttle and doesn't really shop up anywhere else and definately not at idle or WOT or highway rpms.

 

I've had the same issue for over a year. On 5w30 it would rattle nonstop at 70mph (2400rpm) so I switched to 10w40 and its reduced the rattle by 60%.
Makes me think that one of the tensioner/plastic guides are shot. 1600-2100rpm, under light throttle , will almost always cause that annoying sound.

 

Running 91 here in Cali it's highest we have aside from a few 100 octane pumps around my area. I'm thinking it's detonation from how it sounds. Looked detonation vids on YouTube and it sounds very similar to what I've found. Another thing is I haven't changed the spark plugs which from searching this Crouse off action has fixed numerous people's 3.5's. I bought the car six months ago with 160 thousand miles and from the looks of it the bolts on the coils don't have any marks indicating these plugs never been changed.

 

I've switched also to 10w30 with no change in sound. The sound is very annoying and embarrassing to say the least. My old 98 max didn't have this issue now wish I would of bought a 4th Gen at this point.

 

My rattling is very loud at 65 while just maintaining that speed

 

Nice...now where is that located?

 

I have this rattling problem too on 2000 infiniti i30.
It started a couple of months ago.
The dashboard rattles only in drive mode with brakes applied like when you are a traffic light.