Ok so I used the search button and it may not be as good as Google.com but I couldn't find a match to my problem.

I have have been noticing that at low RPM's that there is a rattle coming from what sounds like the engine compartment, passengers side. The only modification to the engine that I have made is installing a CAI, Platinum +4 SP's and removing the black VVT-I cover from the engine. The car is at 18k miles.

I can hear it best when I am turning the car off. I can also hear it when I am sitting at a stop. My RPM's dip down to around 500-600rpm and when I'm idle it almost sounds like the car is running just enough to keep going but almost dies. When I do turn the car off there is a much louder rattle then that of when I'm @ idle. I have also only recently noticed that the rattle is much worse the longer the car is driven. Thus I was unable to produce the issue when I took it to the dealer. Also, when I do a lot of point to point driving, turning the car off frequently, the car has a harder time starting each time I try to start it again.


Anybody else had an issue as such?

 

first off, you took out the best spark plugs on the market and replaced them with some of the worst. Do you have a cel? Can you pop the hood and duplicate it while outside the vehicle and try and narrow it down? Could it be the cai hitting the fender? You mentioned a hard start, just a stab in the dark but im wondering if it is your garbage plugs, try the stock ones. They could be the wrong heat range or gapped wrong, or as ive seen countless times the platnum could have burned off. Swap out the plugs and try and recreate it, and again do you have a cel?

 

sounds like your CAI might be hitting something, or possibly something came loose when you removed the plastic cover and now bumping on something.

Also, did you make sure the new plugs were gapped properly? And I'm not sure if the tC uses a MAFS, but if it does, clean it with some non-residual brake cleaner and see if that helps your idle and starting problem.

 

The original plugs were a lot better quality than what you have now. If it is running poorly, check the gap on the plugs.

If you have a CAI, that may be the cause of your rattle. If you have K&N CAI, it will probably get worse. Look at the bracket on the motor mount, if you have a K&N, chances are it is broken off the motor mount, so the CAI rattles even worse. The K&N is pretty crappy that way.

If the CAI is rattling, it will be hitting the fender opening (where it runs from the engine bay to the fender). There are various fixes, but Dr.Isotope has a very nice, clean looking fix for that. Check this link out

http://doctorisotope.com/index.php?o...d=25&Itemid=29

Good stuff and his prices are incredible.

 

i think i know what he's talking about b/c my car does it too it idles funny at about 500-600 and rumbles all the time "My RPM's dip down to around 500-600rpm and when I'm idle it almost sounds like the car is running just enough to keep going but almost dies." i experience the same thing and i know it's not the intake b/c mine is only short ram and supported with foam and a type of putty i put there its a portion of the hatch rattling but if i touch the gas slightly and bring the rpms up to about 750 like normal cars...then everything stops does anyone know how to adjust the idle or should i have dealer do it? soccerboy i think u might have the same problem does it get worse when you put the rear defroster on?

 

Idle speed is fine. If it is trying to die, then you may have some other issue. The car will idle as low as it can and still run. So some slight roughness (especially when an electrical accessory kicks on) is normal.

 

I've checked the plugs and even swapped back to the stock ones.... no change
I know it isn't my CAI b/c that thing is locked down tight and it's on the opposite side of the car then the noise...

I think IcetC and I have the same problem.

 

werd next time i go to the dealer for an oil change i'm gonna ask if they can raise the idle my pops is a mechanic and when we went to go raise the idle the old fashioned way (adjusting throttle cable) i forgot to tell him that we had drive by wire throttle so im gonna ask the dealer too