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Mar 14, 2026 | 08:52 PM

#11

augustwillo

Drifting

Joined: Aug 2012

Posts: 35

Likes: 4

From: Oregon and Wisconsin

Quote:

Originally Posted by JohnZo

Maybe compression test all eight for comparison, but 30 is way low. Typical for mine is 140 - 160 psi.

More likely than stuck valve, could be head gasket leaking towards the rear coolant passage. Maybe test for exhaust/bubbles in the coolant tank.

Ran a compression test for all 8. Here are the results:

Cylinder | Compression
1: 185 psi
2: 180 psi
3: 170 psi
4: 180 psi
5: 20 psi
6: 160 psi
7: 20 psi
8: 160 psi

Because cylinder 7 and 5 are side by side, it is making me think head gasket. I wasn't thinking this because I barely have any leaks and there is no white smoke coming out the exhaust. Will run the coolant test tonight to see if any exhaust bubbles come up. Kind of hoping I see them, kind of hoping not.