Has anyone tried any cylinder additives like restore? And if you had did it work? I have a 1986 rx7 non turbo that will not stay running when cold. Everyone says its compression, but it runs so good and no smoke at all. Thank you any responses are a help.

 

I replaced a few engines due to low compression causing them to not idle but never heard of it happening only when cold. I doubt compression is the problem if it idles fine at normal operating temp. All the ones i saw idled fine cold but would die at stops at normal temp.

 

No additives will help to restore compression in a Rotary if that is the problem.