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Ok guys,

Just the other day when my car was cold I could here a tapping sound coming from the engine.

It then went away as my car got warm, but then the same thing the next day when my car was cold.

It has now got quiet loud, it doesn't do it when cruising or at idle just under load. I'm not quite sure if its there when revs get over say 4000rpm.

It is a constant Tap Tap Tap and goes with the engine revs.

Now one thing ive done is if i was to take off the plug to the spark plug on cly#1 the sound seems go away (revving it in neutral)

Im hoping it to be the exhaust gasket??? But could it be a big end bearing?

What test should i do to find out?

Any suggestions?

Thanks.

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sounds like a exaust gasket to me esp as it goes away as things heat up . my sons r33 was doing the same thing and i was conviced it was a lifter but turned out to be a gasket . and to the guy above pinging usually happens under heavy load and a few tanks of octane booster wont fix ya prob .

Just been looking at it again today.

Sound definitely goes away in high revs... no bad knock under boost.

I have found 3 missing studs/bolts off the exhaust manifold. So looks to be leaking.

I know what ill be doing over the easter break.

have fun removing the manifold, cost, $200 in all new parts, and a days labour. i just did this on my car. It's dam easy if you follow the nissan manual.

The hardset part was removing the broken engine studs, about 1 hour each.

when we did my sons 3 of the bolts had broken off with the bolts counter sunk . we called a bloke called captian thread he drilled out the broken bolts got the rest of the studs out and cleaned up the threads in about 45 mins . charged 120 bucks but without the proper drills and stuff i would have been there all day .i fitted new studs and gaskets and problem solved make sure you put a straight edge across ya manifold to check if it's warped or not and check it for cracks . i know tangles manifold come off in 2 bits it was snapped right thru .

cheers mid life crisis

What is the price for the gasket and studs?? how many studs do I need? are they all studs or are some bolts?

They are 10mm studs right?

Thanks.

have fun removing the manifold, cost, $200 in all new parts, and a days labour. i just did this on my car. It's dam easy if you follow the nissan manual.

The hardset part was removing the broken engine studs, about 1 hour each.

AHHH the studs are M10*1.25 TRUST ME i got the wrong ones the first time.

Bursons , 12 studs $14 or so. They are good studs too.

A gasket set is about $200 form Nissan, but basically you will need the manifold to engine gasket, manifold to turbo, and turbo to dump if you remove the dump. Also some copper washers and that's all.

yeah pain in the ass this job, i have had my manifold off a few times now and replaced one. I have found that if your careful and use some ezyout fluid (wd40 or penitrate) on bolts that are overly tight you wont snap things, but yes replace all heat soaked nuts and bolts with high tensile ones, makes for far easier Maintenance later on.

Oh and Nissan will charge anywhere from $100 to 150 for exhaust manifold gasket.

I got the high strenght ones form Burson, it was $14 for the main 12 studs, but the 40mm ones no one makes, they are a two thread stud. I went to Nuts and Bolts and got 4 studs to match the manifold thread, same both ends, and nuts to suit, and it was like $2.

Nissan are the ony ones selling the 40mm ones at $10.90 each.

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