Diagnosing engine knocks...
 

You guys probably remember my engine problem that arose a short time ago. If not here's the cliff notes

spark plug ejects.
no start condition w/ various codes.
replace fuel pump
will not idle
fuel injector wide open.
trip to ford dealer-knock appears. 200.oo bill and no progress.
replace injectors, replace cop's, replace fuel pressure regulator.

NOW car idles and drives but there is a knock.

1) any tips/tricks (oil additives that might make it go away)

or

2) any advice on how to diagnose the knock ie. main vs rod bearing or maybe valvetrain...

Thanks again...

Then again it might be "piston slap"... any suggestions greatly appreciated...

is it constant or inconsistant knock? if not when does it do it? you need to explain the situation when it happens..

would runing higher octane or getting is looked at with an SCT XCal do anything?

Sorry... It's like a rod or main bearing knock(I'm guessing). it's constant and not too loud. I hear it all the time. at idle it's noticeable but not annoying. Then as I accelerate, it gets faster and a little louder...

driveability isn't effected other than the noise but I know there's a good chance I'm damaging the bottom end...(main or rod journal)

timing chain may be hitting. that is a known problem. sounds like that could be along the lines of your problem.

You sure?! I've got a 2000 GT. I would have bet it to be rod/main bearing or maybe piston slap or valvetrain (very iffy)

Here's a refresher on what originally happened...

Bump......

So I unplugged each spark plug (one at a time) while the engine was running and the sound didn't change. Then I put a piece of pcv(no hose available) up to my ear and went up and down both valve covers and didn't notice a change in volume.

So I'm thinkin' maybe it's a valvetrain or timing chain thing...

Any thoughts?!

Should I take off the valve covers and inspect "da train" or....????

Okay, this is what I think originally happened when the spark plug/C.O.P. got ejected. When that happened it obviously killed the electrode on the plug, then the COP shorted out either when it hit the fuel rail or when it was bouncing around from all the cylinder air flow coming out the plug hole. When that happened it shorted out the fuel pressure regulator and the fuel pump and the other COP's and the injectors. (how, I don't know) From the repeated cranking of the engine in the attempt to restart it, I got fuel contamination in my oil. What I thought was a rod/main bearing issue seems to be a valvetrain or timing chain issue.

The reason why I think this is I changed the oil and added Lucas OIL treatment and the noise is considerably quieter AND sometime it's gone. I'm thinking it's a semi-collapsed lifter(follower). and the high viscosity oil treatment has helped to pump it back up...


thoughts?

de ja bump

What's the fix? replacement or mod?