Sporadic leak down test results

[patssle]

I ran two leak down tests back to back and got 2 different results on 2 cylinders. I know the engine would be cooler the 2nd time around but one cylinder show better results while the other was worse. Any thoughts to that?

Cyl 1 - 12% then 7% loss
Cyl 2 - 10% then 15% loss
Cyl 3 - 9% then 10% loss
Cyl 4 - 4% then 4% loss
Cyl 5 - 4% then 2% loss
Cyl 6 - 7% then 8% loss

[JFP in PA]

The engine should be warm, and it is not unusual for someone that does not do this test all the time to get varying results due to small differences in finding true TDC on each cylinder.

In any case, you have multiple cylinders that should be bore scoped on the basis of your results.

[patssle]

I ran the test for a 3rd time - I think averaging the numbers out everything looks decent - nothing to panic over. Seem less than 20% loss is acceptable for wear according to the internets.

Cyl 1 - 12% then 7% loss then 6% loss - 8.3% avg
Cyl 2 - 10% then 15% loss then 9% loss - 11% avg
Cyl 3 - 9% then 10% loss then 6% loss - 8.3% avg
Cyl 4 - 4% then 4% loss then 6% loss - 4.6% avg
Cyl 5 - 4% then 2% loss then 5% loss - 3.6% avg
Cyl 6 - 7% then 8% loss then 10% loss - 8.3% avg

Then ran compression test.

1 - 184
2 - 184
3 - 188
4 - 185
5 - 190
6 - 187