I have a 1998 infiniti q45.
Whenever i press my gas pedal above 2000 rpms i hear the rattling sound, it gets faster as i further push the pedal to the floor. It only occurs past 40ish mph. Ive replaced ignition coils due to stalling and that helped alot. The guy that had the car before me replaced the maf sensor in 2006.
Im afraid itll be something expensive and i dont want that.
Rattling noise
Re: Rattling noise
Captain, is this sound relatively new to otherwise lengthy ownership of the car?
Can you pinpoint around what area the rattle is coming from?
One of the most common causes is the exhaust manifold and heat shield area. Gravel, rocks and pebbles bouncing around the heatshield could cause this kind of grief trying to track noises.
However, I'd also encourage you to check the oil level to make sure it's not timing chain or tensioner related. (I don't think this is very common to the engine though).
Just have the car in park and step on the gas and release it to see if it is RPM dependent. It might help to get a friend around the engine bay as you do this.
Can you pinpoint around what area the rattle is coming from?
One of the most common causes is the exhaust manifold and heat shield area. Gravel, rocks and pebbles bouncing around the heatshield could cause this kind of grief trying to track noises.
However, I'd also encourage you to check the oil level to make sure it's not timing chain or tensioner related. (I don't think this is very common to the engine though).
Just have the car in park and step on the gas and release it to see if it is RPM dependent. It might help to get a friend around the engine bay as you do this.
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Q451990
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- Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
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Re: Rattling noise
to NICO! Does it only rattle under a load - like spark knock, or if you were to get it over 2K RPMs going down a hill, would you also hear the noise?-
Captain taco
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- Car: 1998 infiniti q45
Re: Rattling noise
Sitting in the driver seat cruising at 60 on the highway and letting off the gas completely it rattles and is coming from the lower mid engine. It is not new i had adjusted my throttle body cable to rest at higher rpms around 4 months ago But it was doing it well before that. Oil level is perfect just did an oil change 1800 miles ago and am using high mileage (202,568).
It does not matter what terrain im driving, down up or flat itll rattle. And yes when i go up to say 1000 rpms it does not rattle, only above around 2000-2500 rpms+. Once the rpms go up and the gear changes it will stop until i let off the gas completely. Doesnt matter which gear im in either.
Letting of the gas pedal at 75mph and slowing down to 40mph, the rattling will stop, it only rattles above 2000rpms and above 40ishmph
Sitting in park the rattle is there but not as heavy as it would be in driving and at faster speeds.
It does not matter what terrain im driving, down up or flat itll rattle. And yes when i go up to say 1000 rpms it does not rattle, only above around 2000-2500 rpms+. Once the rpms go up and the gear changes it will stop until i let off the gas completely. Doesnt matter which gear im in either.
Letting of the gas pedal at 75mph and slowing down to 40mph, the rattling will stop, it only rattles above 2000rpms and above 40ishmph
Sitting in park the rattle is there but not as heavy as it would be in driving and at faster speeds.
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Q451990
- Moderator
- Posts: 11030
- Joined: Tue Jul 23, 2002 8:21 am
- Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
- Location: Columbia, SC
- Contact:
Re: Rattling noise
If you can get it to rattle in park, a mechanic's stethescope should help you track it down...