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loud knocking under car?

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  #1  
Old 03-19-2011, 07:43 PM
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Default loud knocking under car?

Hey all,

I have a 99 with a 3.8 in it. Auto transmision. I have noticed that when I start the car there is a knocking noise. I have just changed the oil, put new plugs and wires on it, thinking that maybe it was just a cylinder ping. But still no luck. I did the old fashion test on the valve covers and nothing is from them. But crawl under the car and it is louder. Do you think I have a bad rod bearing? And also my SES light is on and the security light too.
 
  #2  
Old 03-19-2011, 10:40 PM
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Are you sure it's coming from the engine? could possibly be the torque converter or if you had the tranny out for some reason recently the torque converter bolts could be loose. just a few other areas to look good luck.
Dave
 
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Old 03-19-2011, 10:53 PM
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I have just recently gotten this car, so no I have not the tranny out yet. I thought it was a lifter problem, but its not. It shifts great without any hesitation at all. The oil pressure is good. right around 50 at start up. It is a constant knocking, even when driving down the road. That is why I was kinda thinking in the engine.
 
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Old 03-20-2011, 12:40 AM
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wrist pin? hope not
 
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Old 03-20-2011, 07:55 AM
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Wrist Pins? Please do elaborate more.
 
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Old 03-20-2011, 11:21 AM
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is it kinda like two clicks if you listen carefully? the wrist pin kinda makes a slapping noise rather than just a tick, and itd be a sound from the underside of the car, make sure you get under there or someone does and check the tightness of everything, if it doesnt go away, youll have to see about having someone more experienced listen to it,
 
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Old 03-20-2011, 07:31 PM
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okay it does sound like to clicks at one time. You said to check the tightness of everything?... like the headers and such under the car, or on the inside of the engine? Or am I just going to have to rebuild? Don't want to drive the car if it is going to kill the motor and leave me stranded somewhere...lol
 
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Old 03-20-2011, 07:41 PM
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jus, headers, exhaust, power steering, water pump, all those things can click if moving incorrectly
 
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Old 03-30-2011, 10:33 AM
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Does the noise increase with engine speed increase? Does it get louder or faster as you rev the engine?
 
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Old 03-31-2011, 06:59 AM
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It gets faster, I did take the valve cover off the drivers side and 4 of the rockers where loose. Going to do the same to the other side and see.
 
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