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Popping Noises From Exhaust On Down Shift.

iseekool

By iseekool,
in Engines & Forced Induction

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iseekool Veteran

iseekool

Posted
Posted

Hi all,

I took my car to great ocean road lately and i gave it a good run - lots of 2nd and 3rd gear action around the bends and hills.

I noticed when I decelerated from higher revs (in a lower gear) there were sometimes muffled crackling/popping noises from my exhaust - personally find the sound pretty cool.

My mates in the car behind say there were no puffs of smoke or flames coming from my car.

I just wanna confirm if this is normal.

R34 - NA - tiptronic - with hi-flow filter, extractors and hi-flo cat - rest of the engine and exhaust is stock.

Cheers

LUME Enthusiast

LUME

Posted
Posted

mine used to do it with normal ngk spark plugs which in fact rooted my spark plugs used to back fire as loud as a gun and pop flames jsut unburnt fuel mines pretty much stock exhassut apart from cannon and a decat hehe shhh but i bought $129 bosch umtimate spark plugs doesnt backfire ne more

N-DAWG Mentor

N-DAWG

Posted
Posted
mine used to do it with normal ngk spark plugs which in fact rooted my spark plugs used to back fire as loud as a gun and pop flames jsut unburnt fuel mines pretty much stock exhassut apart from cannon and a decat hehe shhh but i bought $129 bosch umtimate spark plugs doesnt backfire ne more

Saying shhh about the decat doesn't hide the plates in your disp pic.. :yes:

_bobo_ Mentor

_bobo_

Posted
Posted

yeah my car does it aswel i think it is the plugs tho, i havent had mine changed in a while..but mine is a auto and when ever i release the accelerator at certain revs it makes a lil pop..i too sorta like it.specially when i rock up to lights and down shift sometimes and my exhaust just rumbles tuff and bit of a pop =]

Wacky Dee Veteran

Wacky Dee

Posted
Posted

I get this too on my R34 GTT but mostly before the engine has warmed up properly .. I don't think this is a coilpack issue, I think it has to do with the richness of the air/fuel mix .. most stockies run too rich (I know mine did) plus before the engine is warm I think it runs richer than when at operating temps hence my popping issues on downshifting.

iseekool Veteran

iseekool

Posted
  • Author
Posted
Well normally i think means you gotta get your Coil packs looked at .. how old are yours?

Everything has been recently replaced, about 3 months ago...

The car runs perfectly fine. Not a single issue. It's just this time cause i was driving spiritedly - I'm usually very tame when driving.

central coast person Proficient

central coast person

Posted
Posted

Its the air/fuel mixture ratio. All it is, is that your either got too much air running through the engine or your to rich in fuel. I learnt this because almost all dirt bikes go through this.

Maybe clean your intake and wipe your spark plugs to see if it fixes it. It wont harm your engine if your running rich so you dont have to worry.

iseekool Veteran

iseekool

Posted
  • Author
Posted
check the rear quater on exhaust for blow-by :laugh: mine is plentiful

No blowby "stains" on the back of the car - however i got heaps around the oil cap and PCV area... *brings out de-greaser and rag*

(OO)SKYLINE(OO) Grand Master

(OO)SKYLINE(OO)

Posted
Posted
Its the air/fuel mixture ratio. All it is, is that your either got too much air running through the engine or your to rich in fuel. I learnt this because almost all dirt bikes go through this.

Maybe clean your intake and wipe your spark plugs to see if it fixes it. It wont harm your engine if your running rich so you dont have to worry.

Thats about right.

Since you took it to the GOR for a good (or I should say Spirited...) run, you would have been giving it full throttle majority of times...

More fuel = Need more air to equal out the Air/Fuel mixture.

RBPOWA-(TJ) Grand Master

RBPOWA-(TJ)

Posted
Posted

stock exhaust mine never done it, straight 3inch all the time :) loving it, triptonic auto.

sometimes i down gear to soon just so the revs are higher so it really pops and rumbles. sounds pretty cool coming from a wagon

MissR34 Grand Master

MissR34

Posted
Posted
Sounds great at most times actually to be honest :down: My NA RB25 does it too. Not really concerned.

yeah my girl does it most times aswell, espcially if i take her over 4 grand when changing from say 1st to 2nd and 2nd to 3rd i love it when she does it lol

Kujotk Grand Master

Kujotk

Posted
Posted

its good on a cruise through the gorge around hairpins and you are hearing 15 cars one after another start making pop sounds..... love it

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