Weird compression test result
I just did a compression test on my 1.4 K Petrol.
I did it with the throttle closed - I know that I should have done it WOT.
Anyway, throttle closed I got 120 PSI on #2 #3 #4.
On cylinder #1, I got nothing.
This is not credible because the car runs fine on all 4 (other than coolant consumption) and I can feel a compression puff similar to the other cylinders with my fingers.
My first thought was bad seal, so I cleaned it up down in the spark well. The tester has a rubber ring on it, in good condition. The tester thread isn't that long, not as long as a spark plug.
I also couldn't detect a leak around the spark-plug with engine running. So I think thread is ok.
Any ideas please? I am suspecting IMG internal leak, trying to test HG when this happened.
Engine warm at time.
Also, #1 plug not discoloured or anything.