94 Mustang Gt Cold Knock

GreenStang302

Member

Nov 25, 2011

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7

Florida

Nov 25, 2011

#1

• Nov 25, 2011

• #1

This noise is coming from the passenger side towards the bottom. Only happens when the engine is cold. After the engine warms up, you no longer hear the noise.

It is a fresh rebuild with a little over 800 miles on it. This noise has been there since it was put back together. When I changed the oil, I did not see any metal. The car runs fine.

I know it is not the lifters because it is much too loud and it isn't a tapping sound like lifter noise.

Any suggestions as to what it may be is appreciated.

 

BlackVert

15 Year Member

Oct 3, 2003

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Bethesda, MD

Nov 25, 2011

#2

• Nov 25, 2011

• #2

forged pistons are known to be kinda noisy when the engine is cold.

might you have forged pistons?

 

5.0Droptop

...all those nights we shared, and you're a dude??

Special Agent Mukity-Muck Whats in Charge Round Here

May 15, 2002

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Nov 25, 2011

#3

• Nov 25, 2011

• #3

My buddies Chevy motor with forged pistons does same thing.

 

GreenStang302

Member

Nov 25, 2011

30

0

7

Florida

Nov 25, 2011

#4

• Nov 25, 2011

• #4

No. I did not get forged pistons because I plan on staying N/A. Everything is stock except for cam and fuel pump.

 

79'293stang

Active Member

Jan 5, 2003

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Cedar Rapids, Iowa

Nov 26, 2011

#5

• Nov 26, 2011

• #5

What all went into your rebuild? Did you take it to a machine shop and get everything gone over(honed, cleaned, decked, aligned, etc) and all new parts. Or did you just pull it apart and refresh it reusing all the old factory stuff?

 

BlackVert

15 Year Member

Oct 3, 2003

5,589

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98

Bethesda, MD

Nov 26, 2011

#6

• Nov 26, 2011

• #6

um, ok .....

if the headers are a little loose, sometimes they will let more noise out until they heat up and seal ...

 

GreenStang302

Member

Nov 25, 2011

30

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7

Florida

Nov 26, 2011

#7

• Nov 26, 2011

• #7

Yes, I did take it to a machine shop. I pulled it apart, took the block to a machine shop, and supplied them with all new parts except for connecting rods. They did the whole 9 yards and bored to 306. Then, I put it back together.

I was watching youtube videos and I did not come across one that sounds like mine. This noise is coming from the passenger side only towards the bottom of the block. You can hear it in the car. As soon as the engine begins to warm, it goes away.

It is an AODE and the converter is hurt. Someone had suggested it could be that rattling around but I assumed if it was, the noise would be toward the back, middle part of the engine.

I will check the headers and make sure they are tight. It would not hurt to be sure.

 

GreenStang302

Member

Nov 25, 2011

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7

Florida

Nov 26, 2011

#8

• Nov 26, 2011

• #8

Just an update.. I took a closer look this afternoon. The noise is very prominent when the engine is cool. I originally thought it went away as it got warm, but it does not. It is still there, just not very loud. I waited until it got cool, turned the engine on, and unplugged the spark plugs one by one. The noise was still there until I unplugged the spark plug for cylinder 1. When it was unplugged, no noise, as soon as the wire touched the plug, the noise came back.

So, I have narrowed it down to a problem with cylinder 1, I am just not sure what the problem is. I guess I am going to have to tear it down. Again.

 

5.0Droptop

...all those nights we shared, and you're a dude??

Special Agent Mukity-Muck Whats in Charge Round Here

May 15, 2002

1,785

1,130

233

Indiana

Nov 26, 2011

#9

• Nov 26, 2011

• #9

Do you have stud mount rockers? Is it possible the valve isnt closing all the way and its causing a problem? I just throwing this out there I dont know why it would make a noise other than detonation maybe?

 

GreenStang302

Member

Nov 25, 2011

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7

Florida

Nov 26, 2011

#10

• Nov 26, 2011

• #10

Does anyone know if a rod knock or wrist pin gets quieter after the engine warms?