I've been noticing intermittently a slight drop in power at WOT around 7800 to 9000 rpms. I just changed my spark plugs, which made everything smoother but I'm still getting the high rpm loss of power SOMETIMES.

Had the car about 6 months. 54k then, 66k now. '04 mt all stock. just replaced plugs 3 days ago... this is me from another post:
on my way home tonight, the revs stopped at precicely 9k in 2nd about a mile from home. A code flashed and then remained on. Assuming its the pl0420 again... When I got there, I remembered reading on here about checking the CAT right after hard driving, so I did just that and found it to be glowing orange on the hot side. My buddy looked at it as I redlined it and said it got a little brighter when I did that.

Today: P0300 Random misfire detected Flash/ON 1 or 2 Misfire. This is the code I got when I went to autozone. Lucky for me, the guy who helped me is an RX7 owner and seemed to know a lot about 8's as well. He reved it up and said It's only missing at high rpms, causing unburnt fuel to enter my cat. He said to swap the coils around so that the leadings get switched with the trailings, of course keep the wires in the same locations.

Ok so heres my question with an epic background story build up...I think that since I don't know when the last time the coils were replaced was, and I'm going to have to remove the intake and all that mess anyway, I'll just replace them and the wires instead of rotating the locations of the coils and hoping it solves the problem. Fine. However, it's going to take a week to get them. I have to drive about 500 miles between now and then with possibly a bad coil. That's 500 miles with no redlining for obvious reasons. I can get it up to around 6 or 7000 rpms nicely without fear of bursting in flames.
The question finally...Should I do this coil rotation or drive another 500 miles before replacing them, and/or both?

P.S. I know there are other threads about these kinds of things but this is a specific question that I need a good answer to immediately!!!!You lack Disciplin!!!

 

Consider this... your cat may be done with due to poor ignition.
You mentioned looking at the cat and it was glowing!
The cat is covered for 8yr/80K miles... so you're covered under warranty there.

Swapping the coils may not tell you much of anything.
You received a P0300 code... which doesn't narrow it down to anything.
Swapping the coils may only result in the same code.
Now if the code was P0301, then I would say its fine to swap and then see if you receive a P0302 code.

 

one more question? What are the chances of me getting electrecuted by poking around the coils while the car is off? Things that small with that much energy make me nervous...twss ..but not to me of course...scratch that... is it safe?

 

What do you really plan on doing by "poking" around the coils?
If you don't know what you're looking for or doing, its best to not touch them.
And no... you will not be electrocuted with the car off.

 

That makes sense. So do you think the lack of power at the high rpms is a result of a bad cat? If so, could and would that cause the code? Or, Would a misfire or thousand cause that lack of power? Wouldn't that make it run rough? It stays smooth, it just feels like the engine can't breath up there (in the upper rpm range).

 

Lack of power at high RPMs can be pointed towards the cat, though not saying ignition can be ignored.
Problem with CEL codes is that it may be a good starting point, but can't always be relied on solely.
One system can fail as a result of another.
Your cat glowing is what leans me towards the cat, but with your mileage, the coils could also need attention.

 

I'm pretty sure you can get shocked if the battery is still connected....

 

Yeah... if you touch the battery terminals.... but not by the coils.
You need to read-up on what conditions need to be met before electricity travels to the coils.

 

And yes, the cat is bad. It's glowing because it is breaking apart and the peices are heating up. Gut it or replace it now before you have a car fire. Best case- you blow out some chunky flames... worst case- your car starts on fire and you die... fix the cat and get BHR wires and I bet you'll be fine and get that high RPM back.

 

True, electrisity is my worst subject But better safe than sorry.

 

I've considered gutting the CAT. I've also considered purchasing my friends high flow cat for $50. Only thing is that in NC, I have to pass an emissions inspection in order for the car to remain registered. This is my daily driver. I'm fine with gutting the cat if I know I can pass inspection.

 

Basically... the engine needs to be turning.
The e-shaft sensor reads a positioning plate.
After a certain amount of pulses is calculated, voltage is sent to the coils for ignition.
So if the motor isn't turning, nothing is sent to the coils.

 

Swapping the cat for your friend's high flow is another way to narrow down your problem.
And I have e-check in my area and run a mid-pipe... just swap the cat back in a couple days prior

 

Are the coils not just big capacitors though? Do they store unused electrons?

 

Personally I kept my stock pipe and replaced it when I needed to. Its obviously not the most legal thing to do but what is when you;re having this much fun?

 

No... the coils are more like a transformer.

 

You're like 10 seconds faster than me today... whats your internet speed? LoL

 

Who says its internet speed.. some of us just "spy" around the website

 

Lurking is great fun. Plus then you get to flame first when people ask what the best exhaust is, hahahaha.

 

i'm going the; replace deteriorating factory cat with friends $50 high flow cat promptly tomorrow sometime, wait for new wires and coils to arrive and replace procedure, let all you fellow rotoramigos what the hell transpires from there....brace for the g's with a quick heal toe...

 

Started the day taking off cat and resonator to install high flow cat, ended day with gutted cat. Got all my power back and then some. Nice sound!! Engine light is still on but I think I'll wait till I get my coils to check on that. It was P0300. No big deal at this point I'm guessing since the code is for a ramdom misfire and there seems to be no misfires at all now that I can tell. May just have to reset the ECU. Thanks for everyone's advice.....

 

Since your cat is gutted, you'll receive a CEL for that.
It won't go away unless you have a Cobb AccessPORT and disable the CEL for that particular code.

 

You have to let me know when the fun begins sensei
When you have an expected date planned for everything to arrive, just let me know.
Steve and I are anxious to head down and I have vacation time to burn!
You can always call me if you like too... I'll actually answer the phone

 

Are you sure about this? Because the sensor was located before the honeycomb. The other sensor I saw was before that. How does the sensor know what is taking place behind it in the exhaust flow?

 

Yes

That is the front O2 sensor on the header...

You might want to look at that again....

Maybe this will clarify: