I'm looking into a used 2003 AP1 S2000 with about 15,000 miles on the odo. The price is fair, its in good shape, and the miles are low.

I had a compression test done on it to check the #4 cylinder for damage, and this is how they came out...

#1-175, #2-170, #3-175, #4-175

They tell me the minimum should be 128.

Are these numbers good? Because #2 is low, does that mean anything? Anything to worry about?

FYI, i'm in Canada so not sure if they used PSI or KPA for the test.

Thanks!

 

They're balanced which is good. The absolute numbers may not be accurate. Some gauges don't read right.I wouldn't worry about 5psi.

 

Thanks. I was told with the AP1 to watch for a bad #4 cylinder with a compression test. Sounds like this mill is good to go.

Its the valve retainers that I check for over-rev right?

Thanks,

 

Yes. The intake side.

 

I wouldnt buy it unless it had 230+ in all cylinders.

 

My ap2 motor with 140k has more psi than that! Try another guage.

 

Those numbers are fine. Don't go by absolute numbers, which vary a LOT depending on a number of factors. It's not as if what some will call "low" numbers mean the engine is bad or that it's down on power.

I would take 175/170/175/175 as a good sign, not a bad one.

 

Yea, it does seem kinda low, but like Zdan said, perhaps consistancy between cylinders is more important. I cant see it actually being 175psi with only 15,000miles on the odo.

This test was done by the dealership selling the car. They did say that the minimum (before rebuild) was 128 psi.

What would the new operating PSI be? 230?

Thanks,

 

So the Honda dealership did a compression test on mine before I bought it, car is also a 2003 and I had between 215 and 220 on all four? Is that rare?

 

I'm thinking I might tell them to redo the test with a different gauge...? Its consistent at least, but could also mean that there has been excessive engine wear what would only happen with a high mileage car.

I'm no expert by any mean, but has anyone else done a comp. test and got low numbers due to a crappy gauge or incorrect procedure?

Thanks