Engine Diagnosis

Heads, valves, pistons, rods, crankshaft, etc...

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THAWA
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Engine Diagnosis

Post by THAWA »

Alright here's the deal.

While the engine is cold, or still warming up there aren't any major sounds. Once it gets up to operating temperature I start to hear a BANG sound just about every revolution. I checked the FSM and it says if you hear a knocking once the engine is warmed up and idling to disconnect each injector one at a time. If it doesn't quiet the sound (which it doesn't) then there is something wrong in the heads. The three things it suggest is: really worn lifter, worn cam gear, or worn cam journal. Does anyone have any other ideas as to what the problem could be? I haven't tried listening with a stethescope or screwdriver or anything yet. Any suggestions on what else I should check?
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J-MoNeY
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Post by J-MoNeY »

Could you take a small sound clip of it?
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scottzg
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Re: Engine Diagnosis

Post by scottzg »

THAWA wrote:Any suggestions on what else I should check?
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BAC5.2
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Post by BAC5.2 »

Rod Knock?
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Post by professor »

rod knock should change cadence and severity when you remove spark (or fuel, as you have done)

I'll go for the busted lifter, if there is a huge gap that develops, the valve will get slapped pretty hard. Better to get in there before you trash the heads too
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THAWA
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Post by THAWA »

I suppose I can make a vid of it.

RS heads would be silly at this point.

It doesn't sound like rod knock.

Good to hear someone else thinks it's a head problem.
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Post by douglas vincent »

Get the hose out. Amazing how well it works on narrowing down the damaged area.
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Post by dzx »

You can replace lifters fairly easily, I suggest using his ^ advice and figuring out where it is coming from then you can remove the valve covers and rocker assembly and examine the lifters to see if thats the problem,
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