I have visually checked my coils, spark plugs have been replaced. Only this left to inspect is my cat. My car starts cold/hot perfectly fine. Under normal driving it is fine but as soon as i would increase the throttle to accelerate "Harder" it basically just hesitates and makes a very dull stalling noise. Hard to explain. at first i thought i got bad gas maybe so i burned off a tank and put in some seafoam. Well that was a tank ago and i'm stumped. I think it could be my cat. but i'm skeptical because its not rpm based. its based off throttle increase. Any idea guys?
Car info:
-2004 Rx8
-Coils are 20-30k old but inspected and no burn marks were visible. (I assumed that means they are functioning)
-Plugs are brand new
-Mileage is 87k.
-Fuel pump assembly + filter are two months old


-Thanks everyone

 

Burn marks means nothing, the coils need to be tested properly (search). It could be a clogged cat, it needs to be tested or removed and looked at. Any problems starting it when it is hot?

 

No. Like i said it starts cold/hot perfectly fine. Ill inspect my cat. If that looks like fine go back to my coils.

 

change ur coils, the marks doesn't mean **** (have it or not)

unless it's 100% dead, will start a car fine hot/cold, it's just that when you need it to go fast (hard accel) , it throws the white towel.

I just had another 8 fixed yesterday, car starts fine, but refuses to do hard accel, swap coils to brand new C version, everything fixed.

 

You might be right...got a flashing cell today. Looked under at cat and no red. still goin to do a closer look when i replace the gasket. welp. BHR ignition here i come.

 

Cat was checked and its fine. BHR ignition is on the way.