So I looked around the forum and I couldn't find any information on what causes compression loss. From my previous thread my new engine which only had 15,000 miles has lost all compression. I drove the car hard and it still happened. What causes it? I did oil changes every 4000km and all maintenance was up to date.

 

Build error ?

used housing?

but I think the "biggest" issue is people using a clogged omp nozzle, most people never bothered to clean them while engine is out, takes less than 20 seconds with brake cleaner. yes, they ALWAYS clog, at least anything before S2 will clog.

this is why I always premix ...

 

Rebuild or Mazda reman?

 

There are a few methods of failure in terms of a loss of compression. My first engine died at 22k way back in the day. It was driven hard but never abused, 3000 mile dealer oil changes, etc. It just loss compression exiting the highway one day. The main reason for that is likely poor tolerances during the initial build, the second most common mode was probably carbon build over time that causes seals and springs to stick. It is all here man, read