Here is the original cold start video I took. The exhaust is so loud it shakes the tin roofing on the parking and I feel it thump in my chest.

So tomorrow I'm going to try the steel wool method to try and get the CEL to go away. It's definitely running rich and my mileage is down by a couple mpg. I can smell the gas in the exhaust fumes. It should quiet it down as well. It's been idling around 900-1200 rpm burbling and popping as it sits there. The mechanic is also going to reinspect his work and check to make sure that the 02 sensors didn't go bad. Crossing my fingers.

So this time it is throwing a misfire code. It was P0300. I don't see any definitive fix action for it besides just drive and wait or get a tune. Quick note, the SES light always popped on while I was driving. It seems like most of the others have it pop on during initial startup.

Kinda seems like I'm talking to myself or blogging or something, but just throwing out as I see it. I cleared the P0300 code and came back again. So I'm thinking the only way to get rid of it is a tune. That might take a while to get together. I did have my AFR checked during idle. When it dropped below 900 rpm, it went to 13.5, and when it revved up between 900-1200, it goes to 18 and sits there till the next stutter back down to under 900 rpm. From what my mechanic is telling me, a good AFR at idle should be 14.5, anyone know more about this?

From what I have read that seems a little lean,18? I would go get an uprev tune. Also can you try to repost the video it doesn't seem to be working, thanks.

I'll repost all links to the first post.

So back to the rasp issue I have... Should I remove the cat and put on a resonator instead? It kills me when the car sounds awesome, then rasp rears it's head and sounds like a pissed off chainsaw. It would at least give me the option to run cat or resonator and definitely cheaper than another exhaust. Idk if it's worse inside the cabin than it is outside, I just don't want it.

I would keep the cat on the xyz pipe.

I pulled the codes at Autozone today and had 2x P0300, P0171, P0133, and P0153. Can these all be attributable to my exhaust? No more than 40 miles later, SES is on again.

For the P0300 code, did you handle the MAF sensors at all when you installed the AEM intake?

I had that code up until I cleaned the MAF sensors.

I haven't installed the intake yet. When the SES light kicks on, I can damn near guess when it's going to do it just by listening to the idle. If the idle fluctuates too much, it kicks on. It's been doing it since the install. The shop says when they lengthened the 02 sensors, they extended the wires one at a time to make sure they didn't cross any of the connections. I also told them to remove the o2 sensors before they get crazy with the impact wrench trying to remove the stock exhaust and headers. When I was watching the AFR's the idle would stumble and shows running rich, then the idle would jump over 1k-1200 rpm and show really lean. These codes have so many reasons why they might have been reported, it's difficult to find out what caused them. I'm thinking of just throwing the rest of the parts on just to observe what happens to my existing issues...

Didn't Chuck have similar SES lights? I know he had the PPE longtubes as well.

Can you link the page? I haven't found anything yet

I remember he had some issues with his Z that eventually made him get rid of it.

http://www.the370z.com/intake-exhaus...installed.html

I won't look at replacing them until I get it tuned. Has anyone reported vibrations behind the firewall? Sounds like a heat shield buzzing from resonance at low rpm. I want to find it and choke it. I think I might try that resonator when I have a spare $150. I don't think it's too much out of pocket to see what the differences would be. The headers make power, there is no doubt about it, but I just want to finish cleaning up these small issues already!