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Engine Still Knocking 4kq
In message <0716D052C1CFD0119D280060979FBE9A141BAB@a1.matrix.com.pl> Aleksander Mierzwa writes:
> You say that the noise seems to be coming from the cylinders, but the
> arrow on the picture points to the valve cover. If the noise comes from
> the top of the engine, I would suspect dead hydraulic tappet. If it
> comes from the cylinder area, you may have piston problem. The vacuum
> pump is a good suspect, too.
> > From: David Thoresen
> > I checked everything and the knocking is getting worse... even when
> > idling and standing still it will make a knocking noise, it seems to
> > be coming from the cylinders around the middle of the engine...
Even a dying hydraulic lifter should go quiet after two minutes at 3000 rpm.
If it does, and then the noise gradually starts to fade in and out again at
idle, it's a dying lifter. If it doesn't even go quiet for a moment, I'd go
with the pump. Remove the rod to check. If it isn't the pump, I'd go for a
_completely_ dead lifter. Gudgeon pin knock (little end knock) is IME
extremely rare on I5s.
(I _know_ two minutes is a long time to rev a stationary engine, but that's
what the factory specifies as the test. If you're starting from cold, the
cooling fan should run once before you raise revs to 3000.)
Committee Member, UK Audi [ur-]quattro Owners Club