i think i'm probaly the first to blow my pre-cat on the header(so says the guy at the dealer) thank god for warranties..... bout 600 bucks....

 

how does that happen?

 

precat on the header? would this mean you blew the gasket?

 

how did you do that? also, remember, you have a fed. emissions warranty for 8/80,000.

 

I'm not too sure, but I think running lean may have something to do w/ it.

 

it's all covered under warranty.. but i found that putting in 3 bottles of import laboratories octane booster with full tank of 93 and i unhooked the neg bat. terminal to reset maps.. it was not a smart idea on my part idea ... the car ran great for a while then the check engine light came on.... i thought i fried an oxygen sensor... so i took it to the dealer and they told me i fried the cat

 

why do you need all the octane w/ just a trd drop in filter

 

I don't understand why they're going to warranty that seeing as how it's a direct result of what you did.

The tC uses 87 octane. No more, no less. There is absolutely no performance to be had by going any higher.

 

in fact... there's less...

the high octane makes it slower burning, which hurts power

 

in some cases 89 can be usefull....if your around my area, more often thne not, as SEVERAL times i have had knock in the upper RPMs from bad gas....so i have actually used a decent bit of octane boost and gas treatment, no probs for me

 

sry i haven't update my mods but it's a cai and cat back... it doesn't really do very much for performance but it does make the car run really clean only when it 1 can and 93 it takes away that low octane ping... i was bein stupid but the car ran through the gas and i put in 89 b4 it went to the dealer.....

 

dude...just use 87 unless you notice a consistent need, such as a turbo or s/c. i only use 89 when i notice a little bit of knock, and that was only at almost 6k, approaching red-line, just a fluke in the gas, ony happened a few times, maybe 7-8 max, out of 16000 some miles...