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Discussion Starter · #1 ·
KA24DE, 120-130psi on all cylinders, cold or warm. WOT, good battery. I did only have 2 spark plugs out at a time but that shouldn't effect it. The car doesn't overheat, theres no CEL, the spark plugs are healthy, the oil/coolant are good, it does not smoke, no misfires/weird idling, has power, its literally perfect. I did a wet comp test w/ a teaspoon of oil on 1 cyl and that didn't effect it. I noticed that I got 120 psi no matter if the throttle is open or not. Could this just be a faulty tester thats somehow not sealing all the way? Any other stories of very low compression but the car runs normal? Would you guys drive it until it starts showing actual symptoms? I want as many opinions as possible / explanation for this since Im stumped. If it were valves the car would be running rough, especially at 120 psi.
 

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Your tester is definitely the issue. The fact that the teaspoon of oil didn't change results is the dead giveaway.


You're not burning, leaking or losing oil right?


I guarantee that if you get a different tester you will see different results.
The most important thing is to get consistent readings, if you had some cylinders with lower numbers then I would be concerned.

I would drive that vehicle without any worries. If you are still hesitant, get a leakdown test done. If you are seriously concerned, go get some gauges for oil temperature, oil pressure, coolant temperature. I'd drive that vehicle without issue.
 

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Discussion Starter · #3 · (Edited)
Your tester is definitely the issue. The fact that the teaspoon of oil didn't change results is the dead giveaway.


You're not burning, leaking or losing oil right?


I guarantee that if you get a different tester you will see different results.
The most important thing is to get consistent readings, if you had some cylinders with lower numbers then I would be concerned.

I would drive that vehicle without any worries. If you are still hesitant, get a leakdown test done. If you are seriously concerned, go get some gauges for oil temperature, oil pressure, coolant temperature. I'd drive that vehicle without issue.
So I did it again with all spark plugs out (i previously only had 2 plugs out at a time). Cyl #1 stayed at 120 psi while all the other cylinders went up 20-30psi (this was on a cold engine). Its really weird but yeah Im just gonna drive it. No smoke from the exhaust or any major oil leaks, the oil /coolant level stay clean and the same. If it is actually low comp in a cylinder then I can still drive it here and there until I have time to rebuild, ill leakdown test it soon
 

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Did you do it again with the same tester or a different one?
I'd try to get a different tester on it and see what that says. I think autozone/advance auto rent them out cheaply if not for free.


I know some guys like to bring two compression testers with them to the junkyard when they hunt for engines.

As long as you aren't misfiring and keep an eye on your maintenance you should be ok to drive around. I wouldn't go out racing or strap a turbo to it anytime soon but I'd think you would be fine just commuting.
 

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Discussion Starter · #5 ·
Did you do it again with the same tester or a different one?
I'd try to get a different tester on it and see what that says. I think autozone/advance auto rent them out cheaply if not for free.


I know some guys like to bring two compression testers with them to the junkyard when they hunt for engines.

As long as you aren't misfiring and keep an eye on your maintenance you should be ok to drive around. I wouldn't go out racing or strap a turbo to it anytime soon but I'd think you would be fine just commuting.
It was the same tester. Yeah thats what im thinking. I do want to turbo it eventually and ill rebuild it before, but thats a long ways out. Im only driving this car a couple times a week because its just a weekend car. My priorities are to fix all the other minor issues like the steering rack and surface rust rn. Thanks!
 
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