What to replace Coils & wires or SSV
 

I have a 05 with almost 80K with a second engine installed (factory recall on the first)

After getting new spark plugs and new radiator installed about 1K miles later I noticed a lack of power at the 3000 rpm to 4000 rpm but no strange sounds or funny smells.

I take it into Mazda in San Francisco and they tell me that I need new coils & plugs which they may be right on since they have not been replaced since I got the car. BUT they also tell me that I need a new SSV (which they charge $650 in labor). When I asked how they came to that conclusion on replacing the SSV they said that the computer came up with an error.

My question is; how do you tell if your SSV needs replacing? No dashboard errors displayed during the power loss and not funny sounds or smells came from the engine.

Also does ANYONE know a good, trust worthy repair shop that knows RX 8's in San Francisco ???? Please let me know!

Very simple . If you have someone inside the car turn off the engine while you are watching the SSV - you will see it do an on/off test cycle . If the lever arm moves back and forward - it is functioning .

https://www.rx8club.com/series-i-do-yourself-forum-73/diy-remove-ssv-beta-teaser-video-184663/
I would test your plugs/coils and ssv before replacing any parts.

Also, this is in the wrong forum.