Miata has water in cylinder

I have a '97 Miata, after leaving it covered outside for the winter, I find in the Summer that water is in #1 cylinder, both cylinder and spark plug are rusted. I had not washed the car or the engine. Any clues?

The head gasket may be breached in the area of the #1 cylinder.
Have a compression test and a leak-down test performed to determine if there is a head gasket problem.

Thank you…I’ll hope that this will identify the problem.

How do you know the cylinder is rusted? If water is truly in the cylinder than follow VDC’s answer.

Am I correct in assuming you mean the hole where the plug goes in…the area where the spark plug boot goes down in the head? Do you mean the spark plug is rusty around the porcelain and metal interface? Does the car run normal? If this is the case water/condensation can get under the spark plug boot.

I smear a little diaeletic tune-up grease under the boot lip to insure a tight seal.

I took it to the mechanic to find out why I have to change out spark plugs every summer after storing all winter. They told me about the water and the rust. They scoured out all the rust in the cylinder and replaced the #1 spark plug…I say “cylinder” assuming that’s where the spark plug goes in. The car had been missing real bad and I had just changed out all the spark plugs a month earlier…in that month, the #1 spark plug had rusted. Weird. The mechanics assumed I had power washed the engine and when I told them I hadn’t even washed it, they told me “someone must have”. So they were no help in figuring it out. I’ll keep you suggestion about the boot lip…thanks for your help.