so my engine light comes on and off at times, first time it came on took it to the dealer where i brought my car at. ran a test on it came back with 2 problems:

1)Diagnosed and found cat efficiency code, if light comes back need to take to mazda to diagnosed and cat may be under warranty

2)unable to communicate with solus or DRB in generic scan mode scanned with mac scanner and found P0420 cayalyst efficiency below thereshold, bank 1 downstream 02 rapid voltage changes as if catalyst functioning poorly.

dealer said they cant do much because there not a mazda dealer, so told me to take it to mazda whenever the light come back on. i need my titles so they unplug my engine light for a bit to pass my E-Check, so light was off for like 2-3 days. few days later light came back on, i was busy so i clound't take it right away so waited till the weekend to set a appointment, day i was gonna go engine light was off, happen 2 more time after, so i got **** and took it to my dealer where i brought the car and said look, my engine light comes on and off and you guys found the problem so i want you guys to take it to mazda and tell them to fix it, they say ok, (my engine light was off at this time) 2 days later called me up to pick up my car said it was ready, told me mazda looked at the what was needed and said it was fine so they aint fix nothing, said engine light maybe cause by 2 times:

1)code may be set due to low octaine fuel and warming vehicles at idel

2)advised customer must always use 93 octain premium fuel and not to warm vehicle up to prevent check engine from returning

i always use 93, but i never warm the car up enough i guess, i warm it up maybe 3-5mins max (lost one said warm it up other said dont warm it up), but never start and drive, i redline once a day from what a fourm said to rev it up once a day or when turning off the car rev up to 3.5K for like 5sec and turn it off(dont do this trick kinda scared, lol). so whats a normal drive for a mazda rx8. i have a 2004 RX8 19K mileage. brought it about 3 months now btw

 

you still have factory 8yr/80k emission warranty.
just wait till the light is on then bring it to a Mazda dealer.
they will run test to determine if the cat is shot or not.
at least they did that to mine and it also had the light on and off.

 

snice the one dealer alrdy found the problem y not just fix it (as i said mazda looked at what was needed and everything is fine), but the light havent been on for some time now, o yea and one of the worker also told me its not a normal drive gotta rev like 4-4.5K RMP every shift or something, warranty is over in like less than a month

 

Because the dealer doesn't want to pay out of pocket/warranty paperwork unless they can 100% confirm that it is an outstanding problem. This is typical of some dealerships that are more stubborn when it comes to customer service.

 

Find a new dealer.

 

is this gonna be a big problem if i dont get it fix? or is it because im just not driving it right, i been reving it up like 4-4.5K every gear and light havent came back on, been about 3 weeks i can say

 

^ You should have it checked as soon as possible. In the long run, it will be a problem. Do it until your warranty expires.

 

04 and only 19k? damn I have an 04 with 88K and didn't have the cat issue until recently ..OUTSIDE of warranty, they'll anally insert a 2K quote price for a new cat and see if you're dumb enough to bend over and take it.
Bottom line...have them replace it.