Cvzrx8

will try this also at this moment im really trying everything i possibly can lol
i really wanna rev to 9krpm i miss it.... without misfires or any issues of course.

@!!narotordo

Could very well be that one coil was bad from mazda. I had the same issue happen to me.
I got my mt 8 used with 20k miles. Nothing was changed. They just turned around and sold the car.
I changed the spark plugs and was like dam!
Then I got major miss fire when flooring it. The miss fire was in the mid rpm range. Coils right? wrong! I got two new sets of coils wires and spark plugs and still had miss fire.
I changed the coils and the wire and it was still there.
Now keep in mind before I had the miss fire issue I put some mods on my car. Mid pipe, exhaust, intake, under drive pulley.
So I was thinking its got to be one of my mods. However my friends have the same mods I do but had no issues what so ever.
The only mod I was missing was a ignition coil upgrade. After I installed the upgraded coils I had no more miss fire issues and could feel more power from 45k rpm range and up!
It was the fix my 8 needed.

Cvzrx8

i was thinking maybe a i got a defective coil somewhere, but could i be able to tell if it was defective? if the wires and esps dont do it i might have to try those coils out in january. i just hate throwing money at the car and not solve anything.

@!!narotordo

Could be just one coil. Swap that one out. See if it works for you. If not you know what your options are. GL!

AJ's Shinka

Coils or plugs not in the right place?

Cvzrx8

Got my wires n the crank sensor today cleared the codes
I thought everything was good until I went to redline cel flashing still!!
I don't understand what the deal is! It's very frustarting I'm going to wait till the codes come up
cel fully lit to check the code or codes :'/

Cvzrx8

p0302 cylinder 2 misfire, i was talking to one of my friends and said maybe a fuel issue, could the motor not be getting fuel at the higher rpm? today i did a quick run comparing my car with a friend of mine, my car accelerates smoothly all the way but that time once i hit 7krpm i felt a boost in power very wierd and of course flashing cel, any ideas?

shaunv74

You could try swapping your plugs and coils from the front rotor to the rear and see if the misfire moves to cylinder 1. That would tell you if it's ignition or fuel or something else.

Cvzrx8

Ok I changed the coils well moved them from the front to the rear
n still cylinder 2 misfire is there a way for this motors timing to be off?

Cvzrx8

today i took my car in the stealership to see if they could see what the problem was it resulted in more of a hassle and waste of 95 dollars, they told me that its bank 2 coils are dropping out at the higher rpm and the moroso wires i have on there could also be the cause, and they also told me that other that they wouldnt touch my car or do anything else until i purchased 2 coils and wires from them which was come around $400!!! and also made a huge deal that i had an aem intake and no cat and exhaust telling me its gonna void the warranty on the engine and more blah blah!!!!

shaunv74

Did you clear the code afterwards? The code will stay in the computer unless you clear it with the code reader.

If you're still getting cylinder 2 misfire that tells us it's not your coils. Maybe fuel injectors? did you swap the wires and plugs as well?

Cvzrx8

yeah i cleared them before i went on a run n it came back p0302 n no i didnt swap the wires or the plugs since the moroso wires come like pre cut i just dont know anymore the dealer told me that they didnt want to touch my car more than they have cause aem intake n header back exhaust , in the papers the dealership gave me i guess parts of what they did it said p0300 random misfire and then when the guy talked to me he said it came back as p0302 so im confused maybe all my coils are bad which i dont understand when i just bought all 4! and if it would be the injectors how could i tell if they went bad?

shaunv74

I would try swapping the wires and plugs to confirm that it's not either of those as well. that will definitely tell you if it is an ignition problem or not.

As far as the dealer they are being whiney bitches. Just because the intake and exhaust are on the car doesn't mean they can't figure out what's wrong with it. That being said usually they will tell you to put the stock stuff back on first.

I would put the stock intake back on to confirm that it's not your aftermarket intake screwing with your MAF sensor. The exhaust shouldn't matter.

Try these steps one at a time though so you can figure out what caused the problem.

Faria

so whats is the ending result? was it fixed?

CruelNewb

Might be a bad cat, it happened to me before.

shadycrew31

iTrader: (6)

Bump...

I got a compression test and right after it threw the P0302 code, I checked the wires and one was not seated properly. so I connected it and the code was still there after clearing it. I cleaned the e shaft sensor, double checked the firing order, cleaned connections on maf sensor, and coil packs, and plug wires. CEL on solid after that and flashing at random rpms

so then I figured it must be the plugs I just replaced them. Now the light is off but flashes after random rpms and goes away then comes back again.

No Codes until the compression test.

Thoughts?

shadycrew31

iTrader: (6)

P.S. running an rp supercat and everything else went back to stock.

nx04

I got the aem cai ive been doing some observations , , if i push it till 9k in first i dont get nothing it goes crazy amazing acceleration and what not not a problem , 2nd gear i floor it push it to 9k, straight to 9k it doesnt do it , but when i double tap the gas i do get the flasshing cel , but i shift to third push it all the way to 9k and it goes away shift to 4th and slam the gas and do the double tap all the way to 9k and the cel flashes again , i hold off on the gas and then slow down drop it to 3rd gear , with rpm at about 6 or 7 and accelerate slowly to 9k , and then it flashes and then goes solid ,


every gear for daily driving i shift at 4k , push it everynow and then on back streets or w.e and the light would not come on but when i really open it up is when it flashes its got a mind of its own

shadycrew31

iTrader: (6)

Dude sop redlining every gear. get something to pull codes then search that code.

Razz1

Cyzrx8
It is possible that a bad CAT or O2 sensor may be causing it.

However you replace the shaft sensor. Those things are pretty touchy.

pull out plugs and check for crack on outside porcelin or inside ceramic.

Problem is you had this before you replaced everything.

Check to make sure the intake system is tight and the cap under the TB is not leaking.

These cars run pig rich so misfires are common.

You can try some BBK in the gas tank for the fuel system and injectors.

Shady crew...

You know better than that!!!

Don't tag along your problem with some elses. each car needs to be addressed sepreately.

Make a new thread. If your reply would have stated what you did resolved the issue that would be different.

Your riding on someones coat tails and confucing the isue with the OP.

shadycrew31

iTrader: (6)

I'm pretty sure the OP and myself have the same issue which is why i bumped and posted.

Since there is no solution I was hoping someone could give insight into what could be going wrong.

The only difference between him and myself is I had a compression test prior to the issue starting.

Personally I hate people that start threads asking similar questions over and over and flood the forums with crap. Which is why I didn't start a new thread.

Faria

dang this sux... do you guys premix?? i head Good for OUr engines

Cvzrx8

Hey guys well I still have the issue i've checked everything over n over again so whenever the income tax comes in imma get the bnr coils n see if that fixes it if not imma take off the intake n go back to stock n see if that takes it off cause I've never had a problem running a catless midpipe before so I'm putting everything on the coils n intake of not i just don't know anymore n there would be no point in going to a dealership either, sometimes driving normally I see the cel flash like twice n goes solid so it occurs even when I don't push it now n then, hopefully I resolve this soon because it's been a pain I even bought a secondary car Just in case the 8 one day just doesn't work which is something I dread but never know.
Thanks
Carlos

Razz1

ahh.. Carlos....

Now you mention you are CAT less. That's your issue. You need a AP from Cobb that is tuned.

I suggest you buy from Mazda Maniac.

Out of every thread in 5 years and I have read alomost all of them....

Hardly anyone can have a mid pipe with out a Cel issue/misfire.

SHADY..........

Problem starting when hot and your compression is good along with other components (assuming), is a sign of;

Bad Cat
Starter
EDIT:
Vapor lock, bad gas cap.

shadycrew31

iTrader: (6)

Yea I'm pretty sure mine is compression as it didn't pick up on it until the compression test. I've replaced fixed and inspected all systems that are called for in the fsm to no avail. My numbers weren't to low but low enough for a rebuild.

Carlos get the compression test and lets see the numbers. depending on cranking speed anything 7.0 and lower is on its way out.

the FSM mentions nothing about the 02 sensor being at fault for misfire codes.

But ya never know.