I'm going to buy a compression tester, but need to know the spark plug thread size so I get the correct one. Most have adapters for various sizes. I searched but could not find this specific information. Thanks.

 

i don't have the answer to your question but i rented a compression tester from autozone for free. they only had once choice and it was the correct size for the car. just giving you a heads up.

 

14mm x 1.25.

This is the common spark plug standard thread, and every comp tester in existence I'd imagine will have it.

 

Thanks guys. Just ran the compression test last night.