Got bored at home and did a compression test on a dx motor (d15??) and got the following,
1=115
2=120
3=125
4=170
I left cylinder 4 alone because it looks ok. Added a drop of oil to the others and it raised compression right around 170. If I'm not mistaken, this means the piston rings are bad. The question I have is why doesn't the motor burn oil or blow dark smoke out the exhaust? Oh and I use 10w-30