2004 rx8 no start
 

I have checked everything. From compression to spark to fuel and air. All it will do is turn turn turn turn turn. Acts like it's not even trying to fire. I'm new to rotary. But I am a mechanic for Subaru. Anyway. Anyone have any advice for me? It will not let me communicate with the pcm either for whatever reason. I have checked all the relays as well. Had a buddy who works for mazda do my compression test so I know the engines not totaled. Just need some advice to know where to start next... Will the cps make it do this?

If its cranking at least you know that you have a valid key 😁

Most likely if you have fuel and spark is that it is flooded. If it is a MT try and pull start it. 10mph and let the clutch out slowly in 2nd gear with the key on. Be ready for a smoke show that you will have never seen in a piston engine


If that doesn't work you will need to go back to basics. If you don't have communication to the PCM check the room fuse. It provides power to the OBD port and if it is blown the scanner won't work

The scanner turns on and reads. Just won't pull a code all it says is can not communicate with pcm. I'm hoping it's not a computer. But I don't see it being one of it cranks over and all...I'm at a loss lol. I got the car for 500 bucks so can't complain but it's driving me.insane

Oh I did get it to backfire by dumping a little bit of gas in it lol. But it's getting fuel just fine

This thread has some diagnostic troubleshooting info.

https://www.rx8club.com/series-i-do-...utputs-155947/

I'm having what looks like the same exact problem, same year model '04 RX8 rotary. "sounds" like no-compression in a regular 4 cylinder engine. fast spinning while cranking, very little, mostly no pop or crank like it wants to start. just spinning. Any help is appreciated.

Google "deflooding RX8".
Also check your coils are firing.

In any no start situation, you need to confirm you have spark, fuel and compression.

I agree give it a pull. If you do have spark, fuel, compression then it will start.

New
 

Ok so after messing with it for a hour or 2. It sounds like it's is popping every other rotation. I replaced coils wires and plugs. It makes a few rotations then like a glug or a pop sound. Wish I could share videos lol. I'm gonna try the cps next I guess

Also now I can communicate with the pcm. But my code scanner is a mat co one that was like 250 and dose not do the history codes . And I have to keep pulling the battery out to charge it so it's not keeping codes damn it all.. I'm jw what this backfire type carp it's doing

The battery is probably the problem if you need to keep charging it. This car requires a lot of cold cranking amps to start. Make sure your battery is still good or buy a new one.

Ty
 

The battery was a used one from my work at subaru. When I bought the car it did not have a battery. Anyway I keep fully.charging it with my battery charger. And I was holding off on buying a battery in till.I got.it to run for a few min.. but ill just go buy one on payday. I also orders a cps as well hoping to fix this issue. The hole burping or backfire type sound it keeps making puzzles me

I think the battery needs to be rated for 660 CCA for it to properly start the car. It's possible the battery you are using isnt powerful enough. I'm not sure it will fix the problem completely but it will help. Good luck!

As for the burping, maybe a hole in the exhaust or a vacuum tube or solenoid is broken. Requires a bit of investigation. If you post a vid might be able to help.

Alright I will post a video as soon as I get off work