WTF IS THAT NOISE!?!?!?!!?!? Options

[stud97023]

Ever since ive had my car for some reason when the RPMs are at exactly 1900 rpms, my engine makes a really weird and loud vibrating sound. I popped tthe hood and had my gurlfried press the gas for me so i could try and pinpoint the noise. It seemed like it was comming from the throttle body but im not for sure. Anybody have any ideas? the only mod i have done to the engine is put on cold air intake. Let me know! Thanks!
Jake

[cnelson]

around 4500 - 5300 i used to hear a sound like that.. after a while it just stopped. i think it may of been my heat sheld vibrating.

[stud97023]

Took my heat sheild off and its still making that noise

[stud97023]

Does anyone know?

[K-ESD]

did you check to see if the noise is coming from underneath the engine?

[stud97023]

its not from underneith, deffinatly somewhere near the firewall in the center of the engine compartment

[pandakid]

mine does the same but after i put my greddy exhuast it started doing it.

[Batman722]

it's your exhaust vibrating. There is a bolt that holds it onto rear mount, it's probably loose or gone by now (rusted).

[pandakid]

how long is the bolt supposed to last?

[stud97023]

it's your exhaust vibrating. There is a bolt that holds it onto rear mount, it's probably loose or gone by now (rusted).

Why would it only vibrate at one certain RPM? and not all the time?

[K-ESD]

In physics, resonance is the tendency of a system to oscillate at maximum amplitude at a certain frequency. This frequency is known as the system's natural frequency of vibration, resonant frequency, or eigenfrequency.

In car terms, at X RPM (which is a frequency), whatever is rattling is able (due to it's dimensions, mass, etc..) to move (in wave motion) exactly or close to RPM frequency

[laff09]

Stupid question, but did you check your oil? If your getting low (just before the light comes on), you will hear a loud vibrating sound, depending on how low your oil is affects where in the RPM range it starts. I have this problem every now and again because I have leaky seals and have to keep adding oil pretty regularly.

[stud97023]

Stupid question, but did you check your oil? If your getting low (just before the light comes on), you will hear a loud vibrating sound, depending on how low your oil is affects where in the RPM range it starts. I have this problem every now and again because I have leaky seals and have to keep adding oil pretty regularly.

Just changed my oil today and still making the same vibrating noise at 1900 RPMS.

[Alan]

What Kind of noise is it, like metal to metal of plasic to metal, it is probably something small but I know how enoying It could be

[stud97023]

What Kind of noise is it, like metal to metal of plasic to metal, it is probably something small but I know how enoying It could be

sounds like metal to metal

[laff09]

What Kind of noise is it, like metal to metal of plasic to metal, it is probably something small but I know how enoying It could be

sounds like metal to metal

Valve guides? Do you run the RPMs high a lot when your driving? If so, it causes the valves to wiggle a wee bit, but over time they will wear down the seat and make a vibrating sound similar to the one your describing.

[stud97023]

What Kind of noise is it, like metal to metal of plasic to metal, it is probably something small but I know how enoying It could be

sounds like metal to metal

Valve guides? Do you run the RPMs high a lot when your driving? If so, it causes the valves to wiggle a wee bit, but over time they will wear down the seat and make a vibrating sound similar to the one your describing.

Makes sense i guess, but why would it only be vibrating at certain RPMS?

[Alan]

Its pretty hard to determine a noise from here but If you think it is comming from inside the engine, Its best to take it to someone professional. On the other hand if it is not just feel all the parts around the engine like the air filter and see if the are moving, becuase it might be something loose doing that noise and it does it at low RPM as that is when the engine vibrated the most

[stud97023]

ok so i pin pointed the noise. It is comming from inside that square area on my intake manifold. I have the 94 7afe, and this thing is held on by 4 bolts. I dont have the right tools to get it off but there is deffinatly sumthing inside it vibrating at 1900 rpms. Anyone know what it could be? does it sound bad? and should i open up my manifold and look?