engine noise? needing help and direction

[zoomzoomin07]

okay heres the story took a short 70 mile trip 35 -40 deg outside, drove normally for around 35 miles, car fully warmed up, got on it toying with a honda si and mustang, neways doing lets say over the speed limit, didnt hear any warning, and did not suffer from anytype of cold weather, fuel or boost cut what so ever.

but seem to hear a chattering noise from somewhere in the engine compartment. only under load during accelaration and under boost. I can rev in neutral all day and wont hear a thing.

my first thought was motor and trans mounts checked em out no signs of failure there. more than than my AP is picking up knock counts when chatter accures but not always some time i can make it happen and get no KNOCK, the sound is not associated with rpm of motor, it accures when i reach a certain threshold and stops as soon as i slow down but is not a constant chatter

current mod list TXS Down and race pipe, Magnaflow CBE, COBB SRI, COBB AP, running stg2 v102 sri map and SU rear motor mount

really dont know where to start as far as isolating the fault or noise because the fact that i must be moving, any ideas or help would be great, hope the motor internals are good, my first thought was mounts next a bearing but that would make constant noise and speed up and slow with rpm of the motor

 

[GoFast]

any smoke?? if you are rolling and put it in neutral and give it gas does it make the noise? i know you said in neutral it doesnt make noise but i am assuming you were at a stop when you tried that

 

[zoomzoomin07]

no smoke, havent tried while rolling but I will give that a try, what is your thought process on the following questions.
well maybe a built motor is in my future so that the only positive that could come from a blown motor.

 

[GoFast]

i am thinking maybe clutch/tranny issue or even a slightly bent rod you may feel a vibration in the clutch pedal. however if you only feel it while rolling, i would tend do think more clutch/tranny than engine internals

 

[GoFast]

also, a more positive thought, it may be the idler pully. there have been a few cases of that that going bad too

 

[mazdaspeedster3]

Could it just possibly be something under the hood making the noise and only does while in gear under stress?

 

[Bravnik]

Maybe the rod that holds the hood up was loose?

 

[zoomzoomin07]

kinda what it sounds like, checked it out thought it maybe something loose thats why i just mounts and points working on a mech steth to try and pin point the chatter at idle. mayhave to drop the oil pan and take a look at the rods which i really dont want to that will solidify my need to remove my mods and return to stealership

 

[Zimmer]

sure its not your hood rattling? The rubber stoppers can be adjusted. I had to adjust mine. Awful rattle but I heard the rattle even when rev'g the engine.

 

[714ms3]

I may be suffering from the same thing. I was driving my normal 30 mile trek to work the other day when a 350z wanted to have a little fun. I was already going about 70 and instead of downshifting to 5th, I accelerated in 6th, and as I hit boost I heard a chattering noise. I thought 1 of the fins had come loose in the turbine or something. That is the 2nd time I have heard the noise since owning the car, but everything felt normal afterwards. I have no idea what it is still.

 

[Bravnik]

I may be suffering from the same thing. I was driving my normal 30 mile trek to work the other day when a 350z wanted to have a little fun. I was already going about 70 and instead of downshifting to 5th, I accelerated in 6th, and as I hit boost I heard a chattering noise. I thought 1 of the fins had come loose in the turbine or something. That is the 2nd time I have heard the noise since owning the car, but everything felt normal afterwards. I have no idea what it is still.

That chattering noise you heard was Pinging. If you would have looked out your rear view you would have saw a plume of black smoke I bet. ALWAYS downshift this car when passing.