Exhaust Popping On Decel... Bad!

[bluey33]

Manifold to head hence the 8 studs snapped.

[Bsa]

Those gaskets unless metal are designed to be used once only

[bluey33]

As stated I replaced all studs and manifold with genuine parts. Even new washers and nuts. They are brand new and not re used

[Bsa]

Ok sorry must of miss read

[Manuel Kasko]

Do you have broken gaskets before the dump

How does this cause popping just curious

[bluey33]

It would induce a vacuum in the exhaust manifold and suck air in BEFORE the O2 sensor so it will read lean and richen car up to 'correct'.

I went for good 2 hour drive around surfers paradise and car didn't even look like popping from exhaust. This was with charcoal canister line vented to Atmo. Apart from that only thing I noticed was idle dropped maybe 150 revs.

[zebra]

No it let's oxygen into to the exhaust and allows any unburnt fuel to ignite

[Adriano]

So i guess it is safe to assume under vacuum, the motor is sucking fuel vapour from the charcoal canister into the motor causing a momentary rich pop. Sounds like its working as intended. IMO it seems most skylines do this and its only with a big exhaust you notice it.

[bluey33]

So far it seems so but the issue is intermittent. I dare say if that is the issue it isn't working as it should as when u are decelerating with no throttle your car shouldnt be popping over a dozen times within 3,000 revs so everyone stares at you. If it happens again I will get a recording.

Have had the car over 6years and over 100,000km. It's never played up like this.