i put on the Apexi N1 performance muffler on my 99 eclipse spyder, cut out both catalatic converters, and for some reason my Check engine light comes on.

I believe its because of the O2 sensor, so I installed a O2 simulator. The check engine light is still on and its driving me crazy!!

Do you think a high-flow Cat. will fix the problem?? Thanks for any help you can give :-D

Soldering a resistor on the O2 sensor by the cat might fix the problem. But I fix mine by taking out the bulb behind my gauge cluster. }(

if the check engine light bothers you than id suggest selling your eclipse and getting another car cause once it comes on it will forever haunt you. in time you will begin to gain a certin respect for that light and come to realize that it is our god. for real though if you dont want a light dont mod your car, i lost track of how many resistors ive put in my car to get that light to go out, and its still on i can fix the issue. but in time it will just come back on so i just leave it. i been driving my car for over 3 years now with a cel on and its been turbo'd for about 5 months now. my very first light came on when i changed my exhaust and gutted my cat.

Originally posted by joeck76
if the check engine light bothers you

Its not the light that bothers me... its the sputter when i punch the gas.

I ran a coder though to see what it was saying about my problem, its says that my cars running lean, because of how the O2 sensor is reading. Hense my problem.

I love my eclipse and wouldn't sell it for anything.

I would try another simulator then. Because that one probably is'nt functioning properly. Use the search there is useful info here that could help you. As for the sell your car if you dont like your light deal, dont listen to it. The light is a pain in the ass but you can make it go out. And the moto if the cel isnt on you dont make power is crock because i know of many people who dont have that light and make huge power. Ever hear of bill hahn jr?

if you read what i wrote you would see that i did write that there is a fix for the cel but after a while and a few hundred resistors it gets old and you learn to deal with it. So long as your able to scan your computer and keep an acurate reading of whats throwing the light its not a big deal. just out of curiosity what is your set up? and why did you remove both cats?

Originally posted by joeck76
just out of curiosity what is your set up? and why did you remove both cats?

My car must of been built wrong because mine only came with 1 cat and 1 resinator. Where's the second cat at?

I threw my first Cel's today...yay! I had the car up and running (but not driving) for the first time since last May. Threw the rear O2, MDP, and another emmissions code. But I was expecting them, since I removed all of these anyways...

Good luck with your O2 problem.

My Eclipse came from California they have way tighter emissions over there, I had 4 resinators and 2 cats. Theres more emissions on my car then on my buddys and he has the same car. but his has michigan emissions on it.

But you don't have a 2.4 liter I do. I have a SPYDER GS. you have a 2.0 liter. that could be another reason. why I had two and you have one.

I get some pictures up on this thing when I learn how, and I'll show you My RIDE

I wasn't trying to be a smartazz, I was just wondering why the word "cats" was used. Every 2.0 I've seen has had only 1 cat, but you have a completely diffrent motor, and pcm. I was going off of my own experience, but that won't apply in this situation.

Originally posted by WhiteKnight

Originally posted by joeck76 if the check engine light bothers you

Its not the light that bothers me... its the sputter when i punch the gas. I ran a coder though to see what it was saying about my problem, its says that my cars running lean, because of how the O2 sensor is reading. Hense my problem. I love my eclipse and wouldn't sell it for anything.

If the code is for a lean condition, your first o2 is your problem, not the second one. If the code was p420, then it was the secondary o2. Check to make sure you put the simulator on the second o2 and if need be, change the primary o2.