Engine rattling sound like bogging the engine when not.

[stockysnail]

Here are the symptoms.
-going up a hill in 3rd or 4th gear at 3k rpms willmake a rattling noise like bogging the engine
-every now and then if I rev match on down shift I get a split second of the same noise when the clutch pedal is in
-not sure on this but the older the car gets the easier it is to bog the engine at very low rpms

I don't floor it when the ROMs are low and in a higher gear.
I don't notice and power loss so I don't think it's a slipping clutch.

I'm not sure what it could be but dreading the answer as I have a feeling it's not something simple.

Feel free to ask more questions if more specific in of is needed for a better guess. @Ultramaroon @PitViper @johan @VitViper

[Ultramaroon]

I need to hear it for myself but I have a guess for now. Next time it makes that noise, find the sweet spot to keep it going. Then, without changing anything else, just tap on the clutch pedal. Wiggle it a little.

I thought for a while something was seriously wrong because it's an awful sound. Turned out to be just the clutch master return spring rattling.

Give me a call whenever.

[johan]

I'd have to hear it myself as well, this is a bit odd.

[humfrz]

Has your car given you any codes ..??

Where does the rattling sound seem to be coming from ..??

What, if any, exhaust modifications have you done lately .. ??

Have you changed brands/type of fuel lately .. ??

Any power mods .. ??

humfrz

[stockysnail]

Originally Posted by humfrz

Has your car given you any codes ..?? No

Where does the rattling sound seem to be coming from ..?? In the engine bay somewhere

What, if any, exhaust modifications have you done lately .. ?? Lately nothing

Have you changed brands/type of fuel lately .. ?? No

Any power mods .. ?? Sprintex 210 intercooled supercharger with 70mm pulley, catless UEL, high flow and resonated over/front pipe, Q300 exhaust, Smaller slave cylinder, all the Whiteline bushings you can throw at it, Perrin engine mount, Vented hood which when starting up the car the belt sounds like it slips for a second then it's ok but only when it's rained & parked outside, stainless braided clutch line, Perrin metal intake, Radium catch can, Previously had the Perrin lightweight pulley but put stock back on over a year ago. Trans fluid changed twice and diff fluid once in 60k miles.

Feel free to look at my build thread in my signature.

humfrz

Where does the rattling sound seem to be coming from ..?? In the engine bay somewhere

What, if any, exhaust modifications have you done lately .. ?? Lately nothing

Have you changed brands/type of fuel lately .. ?? No

Any power mods .. ?? Sprintex 210 intercooled supercharger with 70mm pulley, catless UEL, high flow and resonated over/front pipe, Q300 exhaust, Smaller slave cylinder, all the Whiteline bushings you can throw at it, Perrin engine mount, Vented hood which when starting up the car the belt sounds like it slips for a second then it's ok but only when it's rained & parked outside, stainless braided clutch line, Perrin metal intake, Radium catch can, Previously had the Perrin lightweight pulley but put stock back on over a year ago. Trans fluid changed twice and diff fluid once in 60k miles.

Feel free to look at my build thread in my signature.

[humfrz]

Originally Posted by stockysnail

.............
Any power mods .. ?? Sprintex 210 intercooled supercharger with 70mm pulley, catless UEL, high flow and resonated over/front pipe, Q300 exhaust, Smaller slave cylinder, all the Whiteline bushings you can throw at it, Perrin engine mount, Vented hood which when starting up the car the belt sounds like it slips for a second then it's ok but only when it's rained & parked outside, stainless braided clutch line, Perrin metal intake, Radium catch can,.......

DANG! ... stockysnail .......

No wonder that puppy rattles .....

This is waaay above my pay grade ....... hopefully @Ultramaroon can help you sort it out .....


humfrz

[RJasonKlein]

@stockysnail I've been following this thread out of curiosity and I really hope @Ultramaroon nailed it with something as simple as the clutch return spring, because my first thoughts were direct injector or ignition coil failure. Neither are likely because of you don't mention OBD II codes being thrown and because you mention it occasionally happens when rev-matching on downshifts when the engine would effectively be under no load, so I'm stumped. Please keep us posted and good luck!