Bad Coils/Cat failure
 

Hey guys, I need some advice. I took my car to the dealership cause I thought my motor was toast. I was driving and shifted into 4th and there was a sudden power loss and my engine was vibrating, exhaust was fluttering and had a solid check engine light.
I just replaced my Ignition system with these 4,000 miles ago:
I thought they were good coils i did some research and found a thread where one of the guru's on here, confirmed that they would do the trick. It was the best deal i could find for the whole ignition system.

I'm now at 44k, the dealer said they got back code 90300 and 90300 N2?, (i was just on the phone with them). They tested the coils and said all 4 are "arcing" and that the car was running smoothly on the ones they tried. They also said the cat is broken likely due to misfiring and that it will be replaced under warranty.

Where i am confused is that I never once noticed a misfire or loss of power before this sudden powerloss occurred. Never had a flashing CEL, and I noticed increased performance upon replacing the ignition system. So all of the sudden my coils are arcing which caused the cat to fail? Does that make sense? For coils to suddenly go bad after working fine for 4k miles? Or could it have been the failing cat that caused the coils to fail? The dealer wants 88 per coil and 118 for installing them. I can do that myself, but am I in the right to demand money back from the seller? should the CAT (CA Emissions) warranty cover it for causing my coils to fail? is there any way to know?I am going to have my car towed home after they replace the cat and am going to have the coils tested by a trusted mechanic.
I believe they have a warranty, but i'd rather get a better brand this time around BHR or at least something genuinely OEM. I'm glad my engine is okay. I'll post the compression test when i get a copy because I am not certain about how to read it.

If ignition health deteriorates or a cat fails, one will adversely affect the other.

A major catalytic converter blockage could account for the sudden power loss, it happens. But, coil failure is progressive and not all that sudden. Although you didn't notice any powerloss, the coils could've been damaged by the failing cat--even at 4k miles. And the warranty only applies to the cat itself, not components damaged by cat failure. Still, it doesn't hurt to ask the amazon seller about replacements if any of them come back failed from your mechanic.

As for purchasing a new set, genuine OEM is a waste of money, in my opinion. My favorite suggestion to buy them from advance auto with a lifetime warranty, then replace as necessary. The BHR kit is worth it just for the support of one of the best forum vendors and the peace of mind. The choice between the two comes down to convenience and money invested.

First off I am sorry for posting on your thread but the site won't let me create a new thread.

I have an 07 RX8 that has been sluggish to say the least until it stopped starting. I am a new owner of this used car with 89k. Low throttle response before it came to its resting place. Was having very rough starts but no stalling. The battery is fine and when I attempt to start it all you hear is the alternator. The day before it stopped all together I was driving up a hill and I had no power. Crawling the hill at 20 mph. Car is automatic. Need help desperately. Check engine light flashed that night but never stayed on. Thinking it could be the timing belt? Any suggestions welcomed. Thank you for your time.

You need to read the new owner stickies, if you are serious, & not a troll.
Rx8s don't have timing belts.

Ok thank you and sorry for seeming like a troll. Just very concerned

Take it somewhere that can read your codes and lift it to inspect your cat.
Search the misfire stickies after you're done with the new owner ones.
Flashing CEL means misfires, most commonly bad ignition (coils, plugs, wires).
Misfires kill cats. Bad cats kill engines.
Everything you need to know is here if you search.
Good luck!