Mis-Fire problem
 

ok i'll try to explain my problem. when the car warms up all the problems start. when i come to a stop the car shacks and the rpm moves up and down between 900 and 400. i have a hard time going up hill and i get miss fires. also the miss fires happens a lot more when it cold. i have a rx8 2004 with 31000 miles, manual transmission. i've changed the coils, sparks, and engine mount.

hey am22,

I hate to tell you but it sounds like your car has issues. :( Fortunately, thanks to the new 8 year / 100,000 mile warranty, you might be able to get them fixed.

Misfires are most commonly a symptom of bad ignition coils but seeing as how you changed those, maybe the issue is elsewhere. Did you change them? Did you make certain the ignition wires are going to the proper spark plugs?
Are the wires securely fastened to the spark plugs? (they can come loose)

did you use OEM spark plugs? (leading / trailing)

If all of that is fine, then I suggest you schedule an appointment with your dealership immediatly.

You either have a clogged cat or an engine that is loosing compression. Please read this Technical Bulletin VERY carefully (before going to the dealership) so that you can know what to expect

http://www.finishlineperformance.com...4-08-1924g.pdf


good luck, please keep us posted on this. Also, where are you located?

just get rid of the worms

I’ve been to the dealer ship so many times. First time they changed the coils and sparks. Then the engine mount, but now I’m going back again on the 17th. I’ve looked asked around and I’ve heard a lot of different things, clogged cat, fuel pump, and o2 sensors. The dealership is as lost as I am haha :banghead: and oh btw thanks 05rex8 lol

haha, gl ;)

Try resetting the computer, it may have stored a bad ignition sensor profile.

S

Thread title changed to 'Mis-Fire Problem', from the ever popular 'Help!!!'

"Hunting idle" has been posted about many times before, most often a failing neutral switch. Hunting idle and misfires - might be a vacuum leak somewhere.

You know I’ve noticed another thing; there is a weird noise coming from the engine when I’m cruising around at 2500, 3000. It sounds like there is lose metal peace in the engine. It sounds like when there is something in a soda can and you shaking it. Lol It’s not loud but you can notice it.

I've had the same issue for 20000 miles now...dealer can't diagnose the problem. We swapped coils and plugs 7 times, wires 4-5 times, installed a new PCM still nothing. I even swapped the crank angle sensor because the dealer refused to and it helped a little but I still get misfires constantly. Resetting computer numerous times hasn't helped either. The dealer still says there is nothing wrong and insists on throwing plugs and coils at it is the answer. I'm at a loss...hell, even the guys on the team can't figure it out.

The motor in the car now is a rebuild I got under the emissions recall, 1st motor died at 36k I have 31k on this one.

Get a new cat.

Try spacing out the ESS...it works sometimes in these situations

pm sent danno

What if the cat checks fine, like mine has?

Ya my cat checked fine too.

Well on Monday I’m going down do the dealer with the mazda North America operation northeast region district manager to see if we can find out what its wrong with the car. I’ll let you guys know if I find out anything.

^Good luck...did the same with the district mgr here, pretty much told me to get use to it and just have the dealer keep swapping coils and plugs. I hope you get farther.

Thanks man, I’m ganna try to solve this problem ones and for all.

Fire
 

question..............does anyone know if fire shoots out rx8 exhausts standardly?? reason why i ask is because it happened to my brother rx8 PZ and his is standard...no modifications at all!

Ryan

Dude this is a thread about engine mis fires...

And yes, it is possible for flames to shoot out of the exhaust, rx8's run very rich...so, there is some unburnt fuel that can ignite.

Checks fine as in no CEL or MIL code? Or checks fine as in unbolted the cat from the manifold and looked inside and visually inspected?

The cat. can pass the engines test and still be melted and clogged because there are two catalyst bricks. One can be melted screwing up your airflow while the other is keeping your sensors happy.

If you haven't unbolt it and physically look inside.

Checks fine as in, when they inspect it through the service bulletin for the emissions recall. I was not there when it was supposedly checked the 2 separate times so, I do not know if they removed it and checked inside. Here's a question about that though, why would a clogged cat cause misfires, even though there is no power loss when I' running the car all out?

The whole misfire thing sounds more like a timing issue plus a heat issue being as the coils are mounted directly on the engine. I'm gonna try dannobre's suggestion and shim the ESPS (crank angle sensor) maybe that'll do the trick.

that doesn't sound like a clogged cat then. It should lose power as rpm climbs. The Dealers are typically instructed to check the computer to see if the cat. is clogged and usually don't unbolt it and visually inspect. That's the only way to be sure though.

^I ruled out the cat long ago...the thing that gets me is, I actually was in the shop the last time I brought it in for misfiring and watched the plugs, coils, and wires get swapped out and as soon as we turned the engine over the datalogger picked up misfires almost immediately. And this was after the new PCM was installed and had about 100 miles driven on it...we checked the coils with a fluke meter and they were showing readings much higher than allowed.

Still at a loss...I'm hoping once I do my LS2 coil swap/relocation things will get better.

Has anyone ever tried this product out?
Mazsport Ignition Solution http://www.mazsport.net/store/index....t_detail&p=140

There is a whole thread in the ignition solution. I prefer BHR's offering on the matter. I'm def not talking about or dealing with Mazsport anymore.