I have a 2003 RX8 that struggles to start. I was told it needed servicing. I got it serviced change plugs and coils but nothing has changed. Sometimes it even shuts down while driving. What could be the problem? Thanks.

 

Initial possibilities:
- Weak battery
- failing starter
- failing compression
- dirty e-shaft sensor
- failing fuel pump
- bad gas

 

Get a compression test. Start there that will tell you if you've got a healthy engine. Check your CAT to clogged cat could cause this and could have gotten clogged from your old bad coils. If it is clogged don't drive with it it can kill your engine if it's healthy.
Edit
Or start at what RIWWP stated he knows more than I.

 

Ok I'll get a compression test done then go from there. Thanks a lot.

 

Welcome..

The $100 Thread below might help.

At least the ones that start with the word clean. And, grounds..