97 5.4 Engine Knock
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97 5.4 Engine Knock
Okay I know about the piston slap when cold issue, but I don't think that is my problem.
When cold, the engine has a loud knock from the lower engine that sounds exactly like a bad rod bearing. However, when the engine is warmed up but not yet driven the knock remains, until I drive it. I drive for a mile or two and no more knock. Also, when the knock is present and I give it a little gas, the knock will go away until the engine comes back down to idle.
Now what's weird is, today I started it cold and there was no knock at all.
Oil pressure is constant at about 3/4 up the gauge, I'm running 5W-30 motorcraft synthetic blend with a motorcraft filter. Any ideas?
When cold, the engine has a loud knock from the lower engine that sounds exactly like a bad rod bearing. However, when the engine is warmed up but not yet driven the knock remains, until I drive it. I drive for a mile or two and no more knock. Also, when the knock is present and I give it a little gas, the knock will go away until the engine comes back down to idle.
Now what's weird is, today I started it cold and there was no knock at all.
Oil pressure is constant at about 3/4 up the gauge, I'm running 5W-30 motorcraft synthetic blend with a motorcraft filter. Any ideas?
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Fleet Owner
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It's got 86K on it. I kind of ruled out the possibility of the dash gauge being off because the knock sounds like it's only one cylinder and not all of them. The valve train is also very quiet. I'll have to see about getting a pressure gauge in there to verify.
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Fleet Owner
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Turned out to just be the way it was designed. I drove it for a long time and the problem never got worse.
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The 3V engines are famous for cam phaser knocking, usually not a big issue unless it gets worse. Some opts for running 5W-30 oil to reduce the knock, as well of making sure using the correct MOTORCRAFT oil filter, as it has a check valve inside which is very important for these engines.
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