I recently had both of my cats removed due to a plugged drivers side. I installed 02 sims. prior to their removal. The sound is a little raspier than before, which is kinda cool. I want to know if adding sims. and removing the cats is gonna have an effect on the engine or anything else for that matter. Any and all input would be appreciated. Thx.

 

My car has no cats and 02 sims, just like what you did. The sound is nice and raspy, but it tends to spit and sputter too much due to ( i think ) the lack of backpressure. I'm not sure if 02 simms will give varying readings back to the computer, since a real 02 sensor would be changing, making the engine run different based on that feedback.

I also hear that taking out cats will make you lose some low end torque.. but i'm not sure...

I'm probably going to put on some high flow units from Random Technology soon, mainly due to the annoying popppaopopopppbwwaaaaaaa when i downshift...

 

Ive been running rear O2 sims since I put my longtubes in. Ive tried running with and without cats since FLP has that capability. No problems with the O2 sims...just make sure your pre-cat O2 sensors are functioning OK. I can relate to the loud sonic whoas of running no cats...in fact, it made me put the cats back in. The car was simply way too obnoxious for the street. The cats take away alot of the raspiness and popping.

 

Running gutted cats and rear O2 sims will in NO way harm the engine, or anything else. The only thing it might do is cause the knock sensor to pick up false knock if it is really loud.

The PCM doesn't use the rear O2's to adjust anything on the engine. They just let the PCM know if the cats are working. If they aren't, then they will throw a SES light.

Dan

 

If your computer throws a P0400 code for the EGR, dont worry. Just let me know, I got a fix for ya (EGR sim).

 

My car throws the P0400 EGR Code even though I have the EGR Fitting on my longtubes.
What's this simulator you're talking about.
Thanks

 

Yes...I had the same problem with my longtubes, even with all the emissions fittings hooked up. Basically, there is not enough exhaust pulses going to the EGR valve anymore since the EGR tube only connects to ONE primary tube, whereas before it connected to the "collector" at the base of the manifold. The computer detects this as an EGR flow malfunction. Im going to email you a schematic of the simulator with a description to solve your problem.

 

HAHA...Sorry that just made me laugh out loud. Kinda reminded me of that video with all the imports driving through the streets and some guy doing that sound for the engine sound. lol funny. I know exactly what your describing to, I think that's why it made me laugh so much.

 

Great if you can email me a schematic I would greatly appreciate it.
The funny thing is if I leave my IAT module in which tells the pcm its always 37F it doesn't throw the PO 400 egr code.
But if I take it out it does.
Since I'm gonna be running my supercharger soon i don't think I'll be using the IAT module any more.
I'm getting my car inspected in may before they start emissions testing in june here in Buffalo,so I'll have a year to sort out a few other minor codes.

 

SlickBlack Z can you email me that schematic to

ilarion655321@hotmail.com

Thanks Dan