just changed my spark plugs now engine makes a weird noise

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kingtal0n
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Joined: Mon May 23, 2005 2:42 pm
Car: 240sx
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Remove your valve cover and crank the motor over (not start) until you see oil come out of the oil tubes above the cams. there should be 2 straight squirts of oil for each cam lobe.

This has nothing to do with your ticking noise, but it will help diagnose oil issues in the head.

if you see oil squirt like it should, then your head could be ticking due to

A: air in the lifters. your lifters are hydraulic, if they bleed down (unlikelly but it happens) they cause a loud "tick" more of a "clack" and usually its just one or two, because its very rare for a lifter to bleed down.

B: wear and tear (mileage) *or* some valvetrains are just noisy

C: something mechanical not related to the lifters. you may want to try a stethoscope for diagnosis here.

It would also help loads to figure out of the noise is every 360* or every 720* of revolution. if it happens EVERY revolution on the same cylinder for instance it certainly wouldnt be a rod knock, because you usually only get the knock on the power stroke (which happens every 720*) get my drift...

I just re-read your story and it doesnt sound like a lifter problem at all. sounds like you could have a serious problem, you need to do the compression test, then if you can manage do a boost leak test. the boost leak test will help you diagnose power loss, the compression test will help diagnose the engines condition. from there, you can start making progress.

Also, I want your PS pump. email me


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s13-t
Posts: 419
Joined: Wed Jun 18, 2008 6:07 pm
Car: s13 pig nose w/blacktop sr20det

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anyway it culd be the journal bearing in my turbo? none of the seals are blown cause im not smoking. but would the jounal bearing go out slowly, consistantly making a louder and louder noise when spooled but still create 7 lb of boost? a friend seems to think this is the culprit.

im about to just take the car to a tuner shop in town for a diagnosis.

also, kingtal0n you have mail

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redtop91
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s13-t wrote: my oil pressure gauge when warmed up, reads 11psi at idle.... but my dipstick never showed signes of low oil...
Low oil and low oil pressure aren't necessarily the same ya know.

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s13-t
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Car: s13 pig nose w/blacktop sr20det

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redtop91 wrote:
Low oil and low oil pressure aren't necessarily the same ya know.
true. that was me narrowing it down to the oil pump without actually saying so. wasnt a question.

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s13-t
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Car: s13 pig nose w/blacktop sr20det

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k so i think this was causing the loud a$$ sound at acceleration. so the 4 nuts that hold the turbo to the manifold were loose, and the gasket was blown to hell. o and yea... looking into the hole thats what i am assuming the water inlet would be... i can see really gunky material. and found pieces of somthing, i think from the gasket, around one of the banjo fittings. and my turbo has moderate shaft play. i know i need to replace the oil pump. and during that process i can inspect for gunk in the engine itself and if i find some then i guess i get to clean and rebuild so... found a $65 rebuild kit and a $165 brand new oil pump. i will post updates.

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s13-t
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Joined: Wed Jun 18, 2008 6:07 pm
Car: s13 pig nose w/blacktop sr20det

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quick question

seeing as how im going to put the enigine on a stand to swap the oil pump i might as well do some head work.

-so if i replace the stock valve springs with BC do i have to reshim?

-also, since i will be buying a new headgasket do i need to take it to a machine shop and get it decked/cleaned up?


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