rattling noise at about 2500rpms

[marcbh]

i have a rattling noise that happens at around 2500rpms if i accelerate slowly it doesnt rattle but if i give it a little more gas it rattles until it reaches crushing speed then it goes away what could this be your help would be greatly appreciated thank you

[fat honda kid]

sounds to me like a catalytic converter heatshield is rusting away. very very common

[AD5OS]

Yea just sounds like something is loose. Get under your car and start shaking around your exhaust and looking for something loose. I was thinking it might be your valves needing adjusting.

[marcbh]

yeh im going to adjust my valves anyway this weekend i dont think it has ever been done and i need to clean my egr valves and ports but it really dont sound like a mechanical noise but ill check everything tommorrow or this weekend but anymore opionons is greatly appreciated

[dlatino]

i have a rattling noise that happens at around 2500rpms if i accelerate slowly it doesnt rattle but if i give it a little more gas it rattles until it reaches crushing speed then it goes away what could this be your help would be greatly appreciated thank you

i have the opposite problem

when i accelerate slowly it rattles


my car has alot of problems lol

[91dx(r+p)]

mine does that going up a hill at about 3k, but when i got my new muffler welded on the guys there told me that i bottomed out somewhere and had knocked my whole exhaust loose by the cat..all they had to do was heat up the metal and bend it back..so just another idea?

[H22Artman]

i have the same problem and i can say with most certainty that it is not a heat shield.

i just took all of mine off and it still rattles.

its almost like a light lifter noise but its never very consistent and it only does it under load.
light rattling, not tapping, or knocking. doesnt increase with rpm. just rattles for a second and then goes away once you get further in the rpm range.

the best sound i can describe it as:

when you are in too high a gear or on a hill in a 22r toyota truck or a nissan z24 truck and you give it some gas.....

shitty explination sorry. but for those who know what i mean this might be pretty good.

[evil_demon_01]

i have a rattling noise that happens at around 2500rpms if i accelerate slowly it doesnt rattle but if i give it a little more gas it rattles until it reaches crushing speed then it goes away what could this be your help would be greatly appreciated thank you

That sounds like a loose exhaust heatshield, or stones trapped between the heatshield and the body.

i have the same problem and i can say with most certainty that it is not a heat shield.

i just took all of mine off and it still rattles.

its almost like a light lifter noise but its never very consistent and it only does it under load.
light rattling, not tapping, or knocking. doesnt increase with rpm. just rattles for a second and then goes away once you get further in the rpm range.

the best sound i can describe it as:

when you are in too high a gear or on a hill in a 22r toyota truck or a nissan z24 truck and you give it some gas.....

shitty explination sorry. but for those who know what i mean this might be pretty good.

That sounds more like detonation, what engine mods/ecu do you have?

[H22Artman]

That sounds more like detonation, what engine mods/ecu do you have?

no mods on my motor. just a stock JDM 40k pull motor.

i thought detonation too since it seems to be a throttle/rpm issue rather than just a rpm specific issue.

gonna reset all timing/idle/spark adjustments in the a.m.

[marcbh]

i found out what it was it the cat vibrating but ill get that fixed this weekend thanks to everyone for your input greatly appreciated

[19dabeast85]

My car is making a similar noise also......it makes a softer rattle at EXACTLY 1650 rpms, and a louder rattle from 2000-2500 rpms in every gear under any acceleration force. However, it does not rattle when the engine is cold, only after the temps are normal.

I've been thinking it may be my CAT heatshield, but I've got a new catco cat less than a year old and it has hardly any rust on it and the heat shield is a very thick 12-14gauge material. I've thought about getting a shop to weld beads across the shield to strengthen it and prevent vibrations, but not sure if it would work. I don't want to remove the heatshield because water splashed on a hot cat isn't the best thing in the world....

[19dabeast85]

i found out what it was it the cat vibrating but ill get that fixed this weekend thanks to everyone for your input greatly appreciated

Is it the heat shield on the cat or loose internals?

[JunyAccord]

lol it seems we all have that problem. I was thinking it was a bearing of some sort. I have an Intake. Thats it.

the exhaust was replaced.
the cat was replaced.

even after a whole engine rebuild, it still made that noise!

[marcbh]

Is it the heat shield on the cat or loose internals?

it was a lilltle bit of both i took it off at the shop today weilded the heat shield back on and cleaned the inside out the best i could and put it back and it rattles only once in now better than the way it was

[19dabeast85]

Well I just found what was causing my rattling noises! Evidently either vibrations or the header expanding/contracting broke the rear downpipe bracket. I found the broken piece nestled between the DP pipes and oilpan!: