Alright so I'm new to this, and I've had my rx8 for about 4 months now. Problems started up about the first month I had it. Car has 90k miles on it. It's an 04 AT. It had a jumpy idle every once in awhile, it sputtered at high rpm's, and it sometimes wouldn't start back up after filling up gas. I've noticed it takes awhile to accelerate and get up too speed sometimes also. I had a compression test done and the mechanic said it started up at 80psi then moved up to 120 gradually. I know I should have done it from a dealer but I've known the guy forever. I use 91 premium octane all the time. It starts great at cold temp but has trouble on hot starts after driving fun with it. The other day I was driving and it completely lost power on me, it literally felt like half the car was running. I didn't wanna hurt it anymore so I put it on a backroad then it got towed to my mechanic. Today he said he did another compression test for me and it came out to 0. Then he said there was oily sludge on one of the plugs. I just replaced the plugs, wires, and coils about a month ago as well. Any advice? Please!

 

Sounds like you have some pretty major problems. Unfortunately it sounds like the mechanic you are taking the car to doesnt know rotaries. Those compression numbers mean nothing really, a proper compression test should be done at a Mazda dealer or by someone who has a specific rotary compression tester (most non rotary mechanics dont have them). Hot start issues are typical of low compression motors.

Read all of this thread also to gain some more knowledge yourself, knowledge is power:

https://www.rx8club.com/new-member-f...t-here-202454/

 

He is a trusted rotary mechanic with lots of good feedback and reviews and I know many people who have rotaries who go to him. Even though the compression numbers do sound odd.

 

While a rotary tester is recommended for an ideal gage of compression on a Renesis engine, if a competent mechanic with a regular compression gauge gets a 0 reading, it's probably a safe bet that the engine has lost compression.
A rebuild or replacement seems likely.

 

Im surprised this is the case, they should know then that a rotary specific tester is necessary. That being said, 0 compression is a major red flag. A normal compression tester would get some type of reading on it.