There is a fuel pressure solenoid. It's there to help with hot starts. The hose goes from the solenoid to the Fuel Pressure Regulator. You can test this solenoid per the Factory Service Manual.

Also, if the ignition timing or mixture is setup wrong, it can cause issues with hot starts. Review this thread and it shows some particulars. I remember you mentioning you had an HKS F Con ECU. I recommend a Power FC.

https://www.rx7club.com/3rd-generati...-check-924171/

 

I done the test using piston compression tester and yes I did remove the valve from it,also they said you only need to remove the lower plugs from both rotors it's the main thing to know my engine healthy or not the upper once not that important,it's my first comp test so I'm not expert how to do it proply yet but I learn ,and I didn't know what rpm I did the test how I verify that with normal tester not the digital one.all I did put my foot down and fire the engine for 5 sec and my friend read the result on gauge and that's it but I know is not very good result but I have to wait and see how long will last you never know.

 

The less you drive them the worse condition the motor gets in

 

Well the only reason I didn't drive my car for 10months because it's under a project and it's was rebuild a year before that as a racing engine used on track and road in reworx very well knowing people specialised in rotary in UK I don't know if people hear heard bout them so my car only done 3000 mile max since rebuild so I don't really know how quick they go weak and rebuild and stuff .