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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Low compression on 2-3 plugs?

  • Thread starter Thread starter semperfi510
  • Start date Start date Jul 13, 2004

semperfi510

Founding Member
Dec 1, 2001
249
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Fremont, CA
Jul 13, 2004
#1
  • Jul 13, 2004
  • #1
I did a compression and had low readings on 2-3 plugs on the passenger side heads. What could it be cracked rings, head gasket or any other ideas? I am doing a leak down soon just trying to get ideas. It is on my boosted Saleen. Thanks for the info.
JOhnny
 
J

Joel's98GT

New Member
Jan 3, 2004
368
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central OH
Jul 13, 2004
#2
  • Jul 13, 2004
  • #2
numbers please.
 
B

bdcardinal

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Jun 10, 2003
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santa barbara, CA
Jul 13, 2004
#3
  • Jul 13, 2004
  • #3
usually thats a head gasket, please post the numbers.
 

semperfi510

Founding Member
Dec 1, 2001
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Fremont, CA
Jul 13, 2004
#4
  • Jul 13, 2004
  • #4
35 AND 65.
jOHNNY
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
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69
santa barbara, CA
Jul 13, 2004
#5
  • Jul 13, 2004
  • #5
are those the numbers from the leak down or the compression test. if you are only getting 35psi on a compression test than there are SERIOUS problems with your motor.
 

semperfi510

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Dec 1, 2001
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Fremont, CA
Jul 13, 2004
#6
  • Jul 13, 2004
  • #6
bdcardinal said:
are those the numbers from the leak down or the compression test. if you are only getting 35psi on a compression test than there are SERIOUS problems with your motor.
Click to expand...
i think it was 35-45 from the compression test on either 2 or 3. I have had others say they had similar during a compression when the head gasket blew. I have no knocking on my engine though and it still runs ok except for the blow by?
Johnny
 
J

Joel's98GT

New Member
Jan 3, 2004
368
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central OH
Jul 13, 2004
#7
  • Jul 13, 2004
  • #7
semperfi510 said:
i think it was 35-45 from the compression test on either 2 or 3. I have had others say they had similar during a compression when the head gasket blew. I have no knocking on my engine though and it still runs ok except for the blow by?
Johnny
Click to expand...


unfortunatly your not going to be 100% sure untill tear down, but I agree it sounds like a head gasket.
 

semperfi510

Founding Member
Dec 1, 2001
249
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0
Fremont, CA
Jul 13, 2004
#8
  • Jul 13, 2004
  • #8
Joel's98GT said:
unfortunatly your not going to be 100% sure untill tear down, but I agree it sounds like a head gasket.
Click to expand...
I hope so a leakdown might tell me more.
JOhnny
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
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69
santa barbara, CA
Jul 13, 2004
#9
  • Jul 13, 2004
  • #9
ya that is usually a sign of a blown headgasket inbetween those cylinders. looks like youre ready for a rebuild.
 

semperfi510

Founding Member
Dec 1, 2001
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Fremont, CA
Jul 14, 2004
#10
  • Jul 14, 2004
  • #10
bdcardinal said:
ya that is usually a sign of a blown headgasket inbetween those cylinders. looks like youre ready for a rebuild.
Click to expand...
Yup hopefully for know i can just change the gasket.
JOhnny
 
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