- I performed a compression test a few weeks ago and found that cylinder 3 tested out at 115. When I added about 3mL of oil and retested 2 different times with pretty long cranks, it never got above 120. This leaves me too believe there is an issue on the top end. I've started to take the head off. I am currently working on the intake side and have noticed a decent amount of oil that has built up in the intake plenums. The Y plenum actually had a slight little pool of oil where it connects to the mid plenum. Should I now consider an issue with three bottom end too? Also, while in tearing this apart, what extra stuff can I take off the car that won't throw a CEL or is something I can easily spoof? For context, I am hoping to use the car rarely on the street, and mostly for some track duty. Adding a couple pics of the plenum below? Also, any tips on general for taking the head off, and what I should replace? Thanks in advance!