dessidee90

Noticed about maybe 3-5k ago a slight grinding,chattering sound that found be faintly heard towards the back of the engine, between 1-1.7k rpm. No codes ever been thrown, no lost of performance etc. All fluids are fresh and maintained, oil changed regularly, no oil consumption, premium gas only, and definitely not abused.. Possible oil pressure problems??? I definitely hear it slightly while parked and when going slowly occasionally, not constant while under load. Link below

https://youtu.be/5yK1qkYd-ns

Landshark

pre-2012?

dessidee90

Yep it's a 2008

Waste86

Landshark was probably hinting at a timing cover gasket failure. Take it to a dealer and have them do an oil pressure test on it. If you wanted to be really sure about it, have them take off the front timing cover and examine the gaskets.

Kris9884

iTrader: (3)

Yeah, the more I see these the more I don't want to drive my car lol..

si_driver

dessidee90,

Sounds exactly like my bad cats sounded at exactly the same RPM range. Dealer replaced under warranty.

I actually went under the car with the engine running to figure out where the noise was coming from. And was sure it was the cats, dealer confirmed and replaced.

Here is my you tube video. (with the cell phone under the car)

rm2342

hmm, I recently started getting something too, kinda sounds more like an axle, but from time to time I get a faint rattle. Going to have to listen more closely.

What mileage do the cats tend to go? I just flipped past 60k (figures)

Glenn2008

iTrader: (3)

I had some rattling under my car before I replaced my cats with the FI R-HFC's. Now all is well!

Landshark

if its just the heat shields, a couple bucks worth of large band clamps will fix that.

Victory

Same thoughts. Sounds like a loose heat shield. I don't think your engine is blowing up.

dessidee90

Cool thanks for y'all input. I'll do some more investigating, but I was convinced it's from the engine because it's heard at a specific rpm.. hopefully it's just one of the cats, wouldn't it show any symptoms of a bad cat tho?

Landshark

take a long screwdriver, lay on the ground, and poke at the exhaust heat shields under the car to see if any are loose. had a couple on my other car - they can make a horrible racket when the engine is running, usually at a certain rpm range.

dessidee90

Yep this is spot on! I'm gonna get mine checked out. Thanks

Landshark

im sure the dealer would be glad to sell you some expensive new cats, but i'd check to make sure its not just the heat shields ...

si_driver

My cats started going bad at around 55,000 miles and the dealer replaced them under warranty. There were no issues and/or ECU codes just the noise at 1000-1800 RPMs.

BTW I don't know if everyone knows but the cats have a 8 years and 80K warranty.

Under federal law, the catalytic converter are covered for eight years or 80,000 miles

So don't let Infiniti make you pay for yours if you are still within 8 years and 80K.