I'm having a slight problem with my 8 lately
Its an auto 2006 rx8 GT 79,000 miles
At about 5800 rmps until about 6.5k the car is EXTREMELY bogged down and then from 7.5k to 8k(redline) the car jerks and gets up to speed pretty good.

It only happens in 2nd and 3rd gear.. maybe 4th too but I don't want to risk damaging anything by getting it high enough in speed to check.

We seafoamed through the two ports under the hood 2 weeks ago when the problem started and then put a little in the gas tank also (what was left over)

But the problem persisted. So I'm hoping it isn't cabon build up because my aftermarket warranty does not cover carbon build up I redline daily (more than necessary)

This problem is cause sometimes a constant but usually a blinking check engine light.

 

When were plugs,coils and wires last replaced?

 

Plugs and coils at about 65k-69k. Wires... been awhile.

 

Change your plugs and coils. Wires could easily outlast you. Thread solved.
Seriously, check your plugs, if the tips are black change them. Change coils anyways. Report Back what you found out. These are always the first suspect.

 

Gonna have to go get that cel read. We can all guess what it is, and would most likely be right, but need the code.

 

Not true. The wires degrade as well, the connectors get rusty, and as they are the cheapest part of the ignition system and can easily have their connectors deformed from repeated disconnecting/reconnecting on the plugs, they should be replaced at the same time.

My Miata's coils last > 150k, plugs > 45k or so, but the wires only last about 15-20k.

 

Where are you located?
The North America engine warrantee will apply if located so

 

No mention of engine failure yet, and the warranties have never covered ignition (except the powertrain, if someone talks the dealer into covering coils as they aren't listed as a maintenance item)

 

I'll do the wires, I can't see why the plugs or coils need changing, they might barely have 10k on them.. hopefully that resolves the issue.

 

Does anyone know how to check if the cat is bad?
I'm right past 79,000 miles and I think the cat warranty expires at 80,000 so I'd rather not pay for a new cat in a thousand miles lol.

 

So we got the new wires installed and the problem still persists.. somewhat..
No CEL are coming on and the power decrease at higher RPMs isn't as severe.. but still quiet noticeable.

Probably would have been smart while we had it all taken apart.. but new coils and sparks??
They have less than 10k miles on them AT LEAST.. but ran with bad wires I guess. Please tell me it's more likely the plugs lol, them coils are apparently a bitch and a half for us to replace >.<

 

None of the 3, coils, wires, or plugs, is difficult to replace at all. I can replace all 12 components in less than an hour of work. Closer to 30 minutes.

The change of the wires marking an improvement suggests that a cleaner/stronger spark is helping. Yes, I'd change the coils and plugs too.

Where are you located?

 

In Mannford OKlahoma, small town lol.

I can do them.. and luckily as a work study student I'm not allowed to work during intersession lol so I have plenty of time to do them but last time I did them the rear spark plugs were a bit of a pain.. it wasn't as hard as I think it was I'm just being lazy.. of course I have no choice but to get out and do it lol.

I'll pull it all back apart tomorrow and check the plugs and coils.

Plugs.. Brown tips good.. black tips bad right??

and coils... White scorch marks bad correct?

Anyone know a cheap set of coils? $115 was the lowest I managed to find.. cheaper than the last set I bought though lol.

 

Advance Auto Parts usually has the lowest prices via online. Forum vendors are usually just a bit higher than that.

White marks on the coils don't mean much. It's just plastic heating up. You can have them completely white and still functioning correctly, and they can fail with no white at all. The only way to truly test coil functionality is to get a coil tester, pop a plug wire off a plug, onto the tester, clamp the tester to something to ground it, and fire up the engine. The spark is visible in the tester, and it should be steady in color, duration, frequency, etc... If it isn't steady, then the coil or the wire has something wrong, swap a known good wire over to rule out the wire or out the coil.

Plugs are going to pretty much be black anyway, maybe brown if they are fairly new. Not like piston plugs where they should be a light grey. It's more the amount of crud built up on the end. Shouldn't be much at all, if any.

 

Well. In that case it would appear that I'm SoL until I save up some cash. Rx8 is certainly not the car to own as a college student lol.

No problem, I'll just stop driving the 8 until I can just buy all new coils, and I'll check the plugs in the morning for any noticeable problems, and if it's nothing, I'll assume it's the coils. Couldn't have been good for the coils to run on crappy old wires, that for all I know were in the car since it was built... 80,000 miles ago -.- (i've only owned since 40,000 and we were told all that had been changed/replaced, BIG FAT LIE, thanks Nelson Mazda in Tulsa -.-)

Is there any possiblity my problem is caused by a clogged/bad cat? I'm less than 800 miles from my cat being out of warranty.

Any DIY to check the cat for problems? It'll give me something to do tomorrow I suppose lol.

 

Ignition failure usually leads to cat clogging. The problem will be convincing a dealer that the internals are failing. Usually they want a CEL to confirm, and you can get to a complete clog that is damaging your engine and lighting your car on fire and still not have a CEL.

And yes, one part of the ignition failing can accelerate failure for the others. Running a coil that can't fire to a plug is extremely stressful on the coil. And a working plug in the same housing as a failed plug gets fouled significantly faster.

Coils, wires, and plugs typically have an average lifespan of about 30,000 miles till at least one of them fails. Plugs are more likely to be on the short end of that stick, coils can be all over the place, but even if you have 3 coils that will last 50k+, you probably have one that won't.

 

K.
Changed everything, coils, plugs, and wires. Nothing problem still persists.

Took it to autozone to get the CEL read since it FINALLY would stay on and not just flash at me.. it gave a P0300 Random cylinder misfire detected and a P0302 cylinder 2 misfire condition detected?

Any solutions to fixing it w.o taking it to a dealer?

 

Clean the ESS

 

^........worth a shot. When mine gets dirty my car will slightly stumble running up to redline and I get after it right then and clean it.
One time it even through a P0172 low efficiency code.
Now, I clean the ESS, MAF, and throttle body at each oil change.

 

I didn't see anything at all in or around the MAF.. what does clean and dirty look like for one??

And f my life lol. Is there an easy way to get the ess?? That thing was a PIA when we seafoamed >.<

 

I'll see if I can find a decent MAF pick, but to be honest......I don't think that's it.

In terms of the ESS since you seem to know where that is............it's magnetic, so you can just wipe it with a cloth and do it sort of by feel if you have to. If I get the right angle on it looking from the right side underneath the accordian, I can see it. Flashlight helps. I try to clean all of it including sliding the cloth between it and the plate...it's a tight fit!

 

Don't have a MAF pic on this computer, but if you are going to clean it, then all you need is spray MAF cleaner and spray it real good and let it dry out......with MAF cleaner that's real fast.
You will see a brown bulb on one side of the MAF.........then if you look down into one of the side cavities, you will see what is really two wires(they look like pieces of metal though). Spray in there real well..........don't touch them at all with anything........they break really, really easy. Some use a Q-tip, but DON'T!!!!!!! Just spray it real good, turn it over and let it drain and evaporate. I still don't think this is it though.

Have you attempted to clean the butterfly valve in the throttle body?

To be honest, I don't know what all your symptoms are/were........and what you've done to this point. Think Iread you are still getting a misfire code. Check all plug wire connections.............do you have new wires? Remember, plug wires should sort of give you a snap when putting them on...........sometimes it takes more force than you would think. But.......push in the correct place!


And.....Ireally hate to say this, but some coils are bad right out of the box. Had this discussion with a friend today when we did his......................even though it didn't happen to us, it can happen.

 

Just read back and I see you have P0302, so that's the rear rotor.
Clean that ESS and if no good, then concentrate back there on the rear rotor and make sure those plugs wires are on good.
And since new coils, make sure a pin didn't try to back out of one of those connectors.........that happened to me once.
Funny thing is I just read that a big air leak could cause this as well........you sure all hoses are hooked back up and no cracks in hose or nipples?

 

Okay sooo.. My MAF isn't brown.. it's a black bulb? Bad MAF or do I REALLY need to spray it hard? Is Carb N Choke cleaner alright? Probably the strongest spray we own lol

I'll work on cleaning the ess and see if I can't get a good angle to get at it

I wouldn't think it'd be bad coils.. only becaues out of all 4 coils I had before just one, or two went bad in only 8k-ish miles and then a brand new set and out of four I managed to stick it back where the previous bad one was.. Just seems unlikely.

I can't imagine it being the wires, plugs, or coils at all the problem didn't change even in the slightest after changing all of them.

 

Cleaned the MAF and it's got a little brown to it but I'd say it's more black than brown >.<

The ESS was almost spotless (not sure how, never taken it out before, and was WAY easier to clean than I thought it would be). Did the NVRAM reset also.

New plugs, wires, and coils.

Couldn't spot any cracked hoses or any not connected to anything.

No idea what the "butterfly valve" is.. so I haven't done that but willing to try lol.

Anymore suggestions ? If not.. looks like the car is going to be sitting for a while since I don't have the cash to let a dealership poke around like I have been for the past week lol.