ttemple08

Has anyone successfully diagnosed and fixed this issue on their car? I have searched the forum and many people chat briefly about the issue but no one has ever posted how they fixed it. I have changed plugs, coils, ESS and wires with no luck. I am about to change the rear O2 sensor as I was told sometimes this could cause it and after that I would think the only remaining thing would be to replace the cat.

Any help and input would be greatly appreciated.

RIWWP

iTrader: (2)

Have you seen this thread?

https://www.rx8club.com/tech-garage-...t-here-222280/

Misfires are NOT caused by 1 thing. They can be caused by a WHOLE HOST of different problems. Coil failure, plug failure, plug wire failure, compression failure, vacuum leaks, fuel trims, O2 sensor malfunction, MAF malfunction ESS malfunction, exhaust leaks, bad fuel, electrical grounding problems, fraying belts, clogged or stuck injectors, failing fuel pump clogged fuel filter, clogged cat, overheating, localized hot-spotting, carbon caking, carbon fouling, etc... It's a pretty big list.

Basically any possible part of the car that can cause an unexpected change in the fuel delivery, air delivery, or spark delivery, regardless of if the change is up or down, can cause a misfire.

There isn't "1 solution", because there isn't "1 cause".

Yes, everyone is able to solve their misfires, and they usually do. You just haven't landed on what your particular issue is. Although you could have it from multiple sources. Like failing ignition clogged the cat, fried the O2 sensor and damaged compression. That's 4 different things that can cause a misfire, and only fixing one of them still leaves the other 3 causing them. And yes, that sequence is not only possible, it happens far too frequently.

ttemple08

RIWWP- Thanks for the point. Don't know how I missed that thread but it will be a great help.

drifta

Did you ever get your problem fixed? If so, what was it? I have a 2004 GT MT, 82k miles, I recently cleaned MAF, 3/4 tank of gas, redlined daily, and I just had BHR ignition+plugs installed a or two month ago. I had a CEL flash a few times then go off. I went to autozone and they gave me P0302. I plan on cleaning my ESS soon.

Edit: Update: I filled up from Shell, cleaned my K&N panel filter, MAF sensor, ESS, and reset the NVRAM (brake stomp). I'm going to act like nothing happened. However, if it flashes again, I'm going to be worried.

BTiger94

Hello all. New member to the forum. I myself am working through P0302 code. mine only trips cel when I hit 3500RPM. Fresh reman engine, new coils,wires,plugs. I had a P0301 code but found the Mech mistakenly put the injector plugs in complete wrong order.

niteshade247

I had a misfire and it will recall even after you fix the problem as it stays in long term memory. If the problem is really fixed do the 20 brake petal stomp to clear the memory this work for me no more flashing cel

LochnessMonster

Newbie here. I've had my 2006 RX-8 for four months and I have a P0302. I've already decarbonized and changed coils, plugs and wires. Next up is the cat, which melt a quite a bit. My mechanic told me that rotor 2 is having low compression readings, do you know if the cat could be causing that? It's got just a bit over 59k miles, which seems far too low for me to replace it already

drifta

If it's under warranty, I'd take advantage of getting a reman engine. Then I'd take care of it and I think it would last a long while. Sorry I can't help about the other stuff tho.

RIWWP

iTrader: (2)

If "your mechanic" didn't use a rotary engine compression tester, then ignore his claim. If you want to know the health of your engine, take it to a dealer or rotary specific shop (not many out there) for a compression test. Lots of general mechanics out there will always claim a rotary engine failure every time there is the least bit of problem with anything, even if it has nothing to do with the engine. And being a 2006, you might still have some of the 8yr 100k warranty left, so if it IS a failed engine, you can get it replaced under warranty.

Collettey16

did you ever fix the problem ? I got the p0302 last week and can't find the problem. i have a 2004 GT MT, 74k KM, just installed BHR Ignition with plugs a month ago and have no cat, injen short ram and racing beat cat-back .

BTiger94

i to replaced maf,ecs,plugs,wires,coils. my issue was solved after i had replaced my cat, rear cat sensor, and cleaned the plate the coils bolt to. also make sure the coils are evenly spaced. sounds crazy but it helps.

Tobz

Could be your fuel pump. I had a misfire on rotor 2 and it needed a new fuel pump.

hufflepuff

Did the flashing occur at a particular RPM range? I'm getting P0302 but only above 7500 rpms...

UsoFamous

yeah same here i have i also had a p0302 and it will flash if i get in near the redline territory. But its so confusing because it only happens randomly. some pulls are solid and some i get that damn flash. But for me i am noticing that when i let my car sit for like half a day or so and i go back to start it sometimes it will take awhile for it to start. Thats something thats happening more common since ive been experiencing the p0302.

UsoFamous

So im leaning a little towards fuel system like injectors, fuel pump, fuel filter... also i can hear little quick misfires at idol nothing drastic to where i would stall but i can definitely hear it crackle every other few 20secs or so. So im going to try the seafoam in gas tank see if it helps at all.

04 rx8 122xxx

Replaced

BennitBuilt racing coils D585
Cleaned MAF
Cleaned ess
NGK plugs
10mm wires
mid pipe with cat delete for testing purposes ��
ssv solenoid
oils

Loki

iTrader: (1)

Welcome to 2016
Have you checked the cat, coils and spark plugs? If not start there. And don't drive with misfires or you'll be shopping for a new engine.

UsoFamous

Hello Loki yes i know old thread hahah but im all ears to any advice Atm.

So i had the P0302 and i figured i might as well do a full Tune-up. Car throttle response was massive improvement i also noticed there was less back fires while in high Rpms. But.............. still the damn light will blink every now and then while in high rpms. But if cruising theres no problems at all. So i tried switching the coils around and still same P0302. checked all connections all seem tight and sturdy. So tomorrow i will be installing a mid pipe just so i can delete the thought of a clogged cat out of the equation. Im really leaning towards something in the fuel system like they were talking about above fuel pump, fuel injectors, fuel filter ect... So when i drop in back down and take it for a drive im going to run some SeaFoam in the gas tank and see if theres any improvements. And yess ive tried the whole brake reset for the ess and still same outcome.

New Parts

BennitbuiltRacing D585 coils
10mm wires
NGK spark Plugs
SSV solenoid
Oil Catch Can

Parts cleaned...

Ess Valve
Throttle Body
MAF

Loki

iTrader: (1)

Sorry, backfires? There should be zero backfires. That suggests you're running super rich. Get that cat off of there, its chances of having survived backfires and misfires are pretty low.

Can you get sensor data with your OBD reader? See what your airflow g/sec, short term and long term fuel triim, rpm and AFR are on a warm idle. Just an idle, no revving. Post back here.

UsoFamous

Hey Loki Got an update...


So yeah sorry about the info on back fires i had a stock mid pipe and muffler delete so i was getting quite a few a lot of pops from high revs but with stock muffler it wont do any pops at all...

So update on the 8 i installed mid pipe and took it straight over to go buy some seafoam and used half a bottle to Gas tank. Then went over to chevron fueled up with 91 topped off and now im at 130 miles in drove it like a rotary motor loves to be driven (Engine warm of course lol before the hard drive). And so far no blinking check engine light or stored codes...

I hope its the cure but yes i will definitely do another update when i get low on fuel and see if the issue comes back for the haunting.

Nickmma

Hello, Did you ever figure out what the cause was? I misfire when i do pull into fifth gear, I dont misfire in any other gear when doing a pull.

Tobz

Check your fuel pump. It's the most likely culprit here.