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Skyline R33 Compression Results+ Injector Leak?

PagoRB25

By PagoRB25,
in Engines & Forced Induction

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PagoRB25 Explorer

PagoRB25

Posted
Posted

Hey guys i just tested my engines compression (cold) and the results are as follows

Cylinder 1- 160 psi
Cylinder 2- 160 psi
Cylinder 3- 140 psi

Cylinder 4- 145 psi

Cylinder 5- 160 psi

Cylinder 6- 150 psi

Are these good results? Im worried about 3 and 4 as there quite different results to the rest. Also when i pulled out my spark plug from cylinder 4 it had a coating of fuel covering. I havent run my car today however i have primed the fuel system (has aftermarket fuel pump). Could this be a sign of a leaking injector?

Cheers Alex

GTSBoy Grand Master

GTSBoy

Posted
Posted

Could be anything. #3 down together could mean a small leak in the head gasket between them, or less likely but far worse a crack in the head between them. or they could both have sticky valve guides or damaged valve seats leading to poor sealing (by coincidence). A wet spark plug in one or both of them could indicate a leaky injector which could in turn be responsible for causing one of the problems in one or the other of those cylinders.

But really, do you seriously expect to get a diagnosis of something like this over the internet?

AngryRB Grand Master

AngryRB

Posted
Posted

Its not a great result but they are mostly within 10% of each other so probably just acceptable, maybe redo the test a few times and also a leak down test to see if it changes. How does the car drive/idle?

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