Rep Power: 0

So my Civic was once my dad's daily car and it eventually started to struggle moving under its own power. So his response was to compression the cylinders and the cylinders were (in order) 80, 90, 30, 105. Now I am not a trained mechanic and I have no idea what the compression test tells about the engine, my dad's remedy is to take the head off and have it worked on ( I cant remember what exactly he said) but I feel like there's more wrong. Anyone got any advice? I'm a wanna be mechanic and work on cars but I have no idea where to start. I also don't know if this is the right place to ask this, I'm still new to this and haven't had time to look around.

 
Rep Power: 125

There are a variety of reasons that compression could be bad. My first guess would be bad piston rings because the rest of the numbers aren’t great either. Could also be something like leaky intake or exhaust valves. Dry adding a tablespoon of oil to each cylinder and see if that makes a difference. If it does, it means your piston rings are shot.

What’s the mileage on it?

 
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It has 260,230 miles on it. plus its been sitting for a few years

 
Rep Power: 366

probably piston/cylinders wore out and needs a full rebuild
(new larger pistons, bore cylinders, etc.)

 
Rep Power: 221

Potentially much easier and cheaper to put in a used engine for a few hundred dollars