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Ridiculously High Compression

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aspekt9

15+ Year Contributor
344
4
Dec 25, 2005
Boston, Massachusetts
I've been having some overheating issues lately and I replaced the radiator cap but haven't done the thermostat yet. In the meantime I figured I would do a compression test to make sure it wasn't a blown head gasket. These were the results:

214, 214, 210, 210

This seems WAY too high than the Standard 192 for a factory NT. Is this a huge build up of carbon deposit I don't know where to go from here.
 
I would do a coolant flush if your coolant doesnt look to clean or havent been done in awhile. Thermostat is a good idea to change. The numbers arent to bad. Put some seafoam down the throttlebody when running. That would get rid of the carbon build up.
 
check for carbon deposits . hope this helps.Compression specifications



=> 14 psi maximum difference between cylinders
1G (90-94) T/E/L 1.8L NT engine 2.0L NT engine 2.0L Turbo engine
Compression ratio 9.0:1 9.0:1 7.8:1
Standard compression185 psi 192 psi 164 psi
Service limit 131 psi 145 psi 121 psi

2G (95-99) T/E 2.0L NT 420A engine 2.0L 4G63 Turbo engine 2.4L NT Spyder engine
Compression ratio 9.8:1 8.5:1 9.5:1
Standard compression 170-225 psi 178 psi 192 psi
Service limit 100 psi 133 psi 146 psi

Galant (89-93) SOHC 8v engine SOHC 16v engine
Compression ratio 8.5:1 9.5:1
Standard compression 178 psi 185 psi
Service limit 125 psi 139 psi

Galant (89-93) DOHC pre-91 NT engine DOHC 92+ NT engine DOHC Turbo engine
Compression ratio 9.0:1 9.8:1 7.8:1
Standard compression 192 psi 220 psi 164 psi
Service limit 137 psi 159 psi 114 psi
 
doesn't seem too far outta whack. i would say like the other guys... run some seafoam thru the car and see what it does. then report back with your results. would also give us all an better idea of how good it really works, numbers wise.
 
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