i think the dealer is f in me over
 

i took my car in for a cel and most likely fried catalytic converter. i still have the powertrain warranty (not thats its real relavant) and i also know of the federal emissions control warranty (which probably is relevant).

anyway my problem is loss of power and stalling occasionally after doing some highway driving. i've also seen part of my catalytic converter glowing red. i took it to a dealer and the only problem they are coming up with is that my air intake wasn't assembled correctly which was causing the car to run lean, therefore overheating my cat. but now i'm worried that because of that problem my catalytic converter is fried. i know that they can get hot but once they are that hot the "honeycomb" inside of them starts to deteriorate and melt. so now i'm thinking that they are avoiding mentioning that to me because they don't want to have to pay to replace it. (i've heard the cats are something like $1100.) I'm also now expecting that the cat is either going to work better or worse because it got messed up (i'm expecting worse because it is damaged) and its going to throw another cel because the emissions at the o2 sensor (behind the cat) are going to be different than what the computer is programmed to accept..


all discussion welcome..

if it's an aftermarket intake, you're better off just letting them fix that problem and taking the cat to another dealer for warranty work when it fails. i say take it to another dealer for the cat because they will try to void your warranty due to the failure being caused by an aftermarket part. Also, you should return to stock before taking the cat to the other dealer.

if it's not aftermarket, they're not trying to get out of paying for it, but they won't replace under warranty until it fails. you'll just have to wait it out.

alternatively, you could let them fix the intake, then you could swap the cat for a catless midpipe.

there's probably other options too.

take it to another dealer.

So... the dealer is saying the intake is assembled wrong and running lean.
Lean = more air than fuel. I'm curious how this would happen if the MAF sensor and throttle body are still in 100% working order. Anyway....

Assuming that the intake is causing the car to run lean... how does pushing more air and less fuel through the cat ruin it and cause it to glow red hot?

Interesting questions that I would love the dealer to answer.

You read my mind. i've been thinking of that also i just forgot to mention it when i wrote the first part.

also my intake is stock so i'm also curious about how it became "unassembled properly."

and i guess your right about not having to replace the cat until it fails. but as it is it shouldn't be long before it throws a cel when the emissions aren't correct.

i'm calling the dealer soon today to ask them about the cat and how running lean is causing the cat to glow. i'll post again after the phone call.

Get an RP super cat.

Do not go Cat less, its against the law and the Obama police will come get you.

The sky is falling in due to your cat warming up the air.

Then you can buy a 3 cylinder from GM after Barack forces them to build econo boxes :)

Leaner (more air) ALWAYS causes an increase in temperature in any engine. And in a rotary, it can cause other problems to the engine itself...

Don't believe, here's a home test...basically, start a fire. Now, without adding any additional fuel, blow air into the fire. What happens...? It gets hotter... And if you want to REALLY get it hotter, throw a cup of liquid oxygen on the fire. What happens...? It gets a helluva' lot hotter, flames grow in an instant, and you lose all your eyebrows & nosehairs, at a minimum...

Without knowing the codes the computer stored, my best guess is, at highway speeds your engine couldn't get enough air for the MAF to compensate the fuel flow enough, so it ran like crap at those speeds & stalled. And the catalytic converter ran hotter, because it wasn't getting a rich enough exhaust mix to keep it cooler.

Mazda isn't going to replace your catalytic converter until it fails, though. As long as its working, there's no need to replace it. Emissions warranties are for what, 80,000 miles (IIRC); so unless it goes out before then, they aren't going to replace it. If it goes out after that, replace it with an aftermarket one and save yourself a big chunck of $$.

I agree that leaner increases engine temps... but my understanding of why our cats often fail is because the 8 runs pretty rich, and this unburnt fuel hits the cat (which is already hot) and burns/ignites there which eventually ruins the cat.

I could be wrong in this assumption though.

i have a intake and have no cel. i rest my ecu before i started the car after the install and no cel. if you dont reset the ecu its not going to adjust itself and to the new air flow. thus causing problems with the air fuel ratio.

Vyndictive: thats why you take off the cat and put on a midpipe and put the cat on when you need to get smogged or take the car to the dealer. :D:

alright i just got off the phone with the dealer. i talked directly to the mechanic that worked on my car.

according to him it is normal for a catalytic converter to glow a little after a long drive. i'm not so sure about that fact but if my cat goes in the near future like i expect it to its still under warranty and i can take it back. i'll worry about that when i need to and i'll def consider that catless midpipe. that idea is just growing on me. the reason (according to the mechanic) that the maf didn't correct the problem is because the air intake had a leak between the maf and the engine so the engine was getting twice the amount of air it was supposed to and the maf couldn't correct it. he also says that an engine running lean will run extremely hot so that would've been the problem i thought i had with the cat. i think thats all that was in the conversation.

thats good, and go midpipe you'll love you 8 even more. also the 8 runs hotter than a piston drivin car so getting glow from your exaust is tipical for the 8. we dont shoot out flames for nothing. oh yeah with midpipe flames out the tail pipe is fricken awesome!