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Normal PSI on compression test?

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#1
Was wondering what the normal range for PSI is on a compression test. Only had time to do one cylinder before I leave for work. It was my problem cylinder(the one missing) was reading 130 PSI but wasn't sure what it's supposed to read.
 


TyphoonFiST

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#2
Was wondering what the normal range for PSI is on a compression test. Only had time to do one cylinder before I leave for work. It was my problem cylinder(the one missing) was reading 130 PSI but wasn't sure what it's supposed to read.
As the Engine wears ....it will start to lose compression. It's the nature of the beast. All 4 Cylinders should be 10-15% of each other. Measure them all and let us know the results.

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OP
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Thread Starter #3
As the Engine wears ....it will start to lose compression. It's the nature of the beast. All 4 Cylinders should be 10-15% of each other. Measure them all and let us know the results.

Sent from my SM-N975U1 using Tapatalk
actually looks like I was reading it wrong. 140 PSI across the board, when I pulled out spark plug two it was loose, thinking it may have been too loose to be firing, but they were the original spark plugs ive got ngks coming in.
 


CarGuy

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#4
actually looks like I was reading it wrong. 140 PSI across the board, when I pulled out spark plug two it was loose, thinking it may have been too loose to be firing, but they were the original spark plugs ive got ngks coming in.
Equal and the number seems good to me. The lose plug may have been your issue. Depending on how lose you could have been losing compression in that hole or just causing the misfire. How did the plug look on that hole compared to the others? I'd tighten it all down and try to start it up again.

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TyphoonFiST

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#5
actually looks like I was reading it wrong. 140 PSI across the board, when I pulled out spark plug two it was loose, thinking it may have been too loose to be firing, but they were the original spark plugs ive got ngks coming in.
Make sure to Torque them correctly* it's 13 ft lbs. If my memory serves me correctly. DO NOT just give them the old heave ho.

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OP
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Thread Starter #6
Equal and the number seems good to me. The lose plug may have been your issue. Depending on how lose you could have been losing compression in that hole or just causing the misfire. How did the plug look on that hole compared to the others? I'd tighten it all down and try to start it up again.

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I want to but the battery died from doing the compression checks and sitting on the side of 95 haha, I don't have a charger to charge it and am heading out of town at 8 AM EST. The spark plug was wet with fuel I'll make sure to update when I get back on tuesday;
 


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