Bogging bad sound on startup missfire etc.
 

First off, sorry if this has already been discussed. I've had my 8 for about 6 months now and just about everything i could ever wonder has been beaten to death in here :p

respect for the rotary gods who actually know there sh*t in here as well.


Okay so when i start up my car sounds low and "bogs" best way to explain it. Usual symptoms as well, cranks a few times before it fires up & semi rough idle. Sounds almost like only one rotor is firing or something. Lasts anywhere from 30s to 2m. I've tried giving it a bit of gas (holding at 2-3k rpm) to see if it was just running a bit lean. Has no positive effect & when the sound goes away, if I'm holding the accelerator, steady, it spits & the rpm jumps up like something just unclogged. Seems to be linked to cold weather. -10 to -20 around here for at least 5 months of the year. The main reason im worried is that it feels as though the power is slowly decreasing over time.
** when it started at 58k i had a "random missfire" and "cylinder 1 missfire" error code (can't remember the actual code) but car seemed to be running fine (still is for the most part) and didn't do anything about it right away cause i was a stupid nub.

04 rx8 GT Japanese made (vin) 70K km odo. have had this problem since about 58k
Plugs and wires & new cat at 60k. original coils (i think). All recalls done (checked VIN with Mazda Canada). @69k air pump disconnected (started chirping, took out fuse and replacing bearings atm) seafoam every 10k, starting premix soon. Always use 91 or 94. red line every day. oil change every 3-4k w gtx and regular top ups of course. 1 flood prior to plugs and cat change when i first got it. No CEL related to startup just air pump atm.

Otherwise lots of power, sweet handling, i love this car. Total rotor junky in the making here. Ladies love it, i love it. need i say more? Top Gear quote "I'm not sure whether this car runs on petrol or double cream" XD

step 1 get car running smooth and perf
step 2 molest intake, exhaust, and SC with pettit
step 3 try not to lose licence

Sorry nobody got back to you on this one. I have the same problem and haven't found an answer yet. Did you ever find an answer around here?

The OP's issue was almost certainly coils if they were original at 70,000kms.


If you have 70,000kms on your coils, then it's probably your problem as well.


Otherwise, you will need to be more specific.

A) check my new owner's thread: https://www.rx8club.com/new-member-forum-197/new-potential-owners-start-here-202454/

B) as it notes in there:
Questions we CAN answer:
Most issues that the RX-8 faces are easily answered when you post detailed, descriptive, and accurate explanations of what symptoms you are having with your RX-8. Many of our issues share common symptoms with at least one other issue. Several of the really common issues share MOST of their symptoms with another problem. So when you post: "power loss?" We can't really tell you what is going on. We can only throw the book of possible issues at you for you to figure out.

The amount of assistance you receive is DIRECTLY associated to how much detail you provide!

So what do you need to share?

A) Break each issue you are seeing out by itself. For each of these issues, detail what RPMs it occurs in, and what RPMs it doesn't. Detail how much throttle you are giving when it occurs.
B) Detail what the ambient temperatures are that you are seeing, what the gauges are doing.
C) If you have a CEL, GIVE US THE CODE! (most auto-parts stores will pull the code for free for you. Otherwise, you can buy a code reader for LESS than the dealer's diagnostic price, giving you a discount on that one, and free code pulling for the rest of the device's life, across every car you own) (Hint, search with Google and site:rx8club.com <CEL> before posting. You will probably find your answer.)
D) Detail any possible modifications or repairs that have been made within the last 3,000 miles, even if it seems like it's not related.
E) Detail the age and mileage of the car, and what maintenance history it has been on. NOT just "it's gotten regular maintenance" because there are wear items that are not part of "regular maintenance" for dealers and most shops.
F) Since many issues are ignition related, and you are going to get asked, give us the mileage and age of ignition coils, wires, and plugs.
G) Detail out when it DOESN'T happen. This is just as critical as when it does!

Another thing to keep in mind is that unless you are being a complete jackass, and unless the person responding to you is ignorant about the issues, our answers are going to be pretty accurate, if not dead on. Even if you don't like the option. We have no stake in your finances, no stake in making money off of it. We DON'T like to see unhealthy or busted 8s. So if you choose to ignore our recommendations, do so at your own peril, and don't come whining to us that you shoveled money at the problem that was completely unneeded.

Hey godfather Pearl, you should make this your sig! :rollingla:

Mine has the same symptoms. Mazda dealer checked it and after new plugs/coils it still miss fires on most cold starts causing a check engine light. Back to the dealer and they called Mazda and determined it to be a leaking fuel injector/injectors on the rear rotor. Apparently the leak occurs after shut down and a cold soaked enging has trouble clearing it. Very expensive for them to fix it at $1500+ for the three injectors on the rear rotor and $2200+ for all six injectors. The mechanic also said I may get lucky with some fuel injector cleaner and "run the piss out of it"..... I've had some fun doing that and the thing does seem better although it is not nearly solved... Once warmed up it runs perfectly. Killing the engine by pulling the fuel pump relay, then ignition off, then plug the relay back in, seems to help a bit. I may try to get at the injectors myself (still a pricey fix for new injectors). The mechanic says "it's a bitch" to get at them so I'm still mulling over what to do. This is a 2006 on it's second engine (2007) 85000 miles

Hey, ive just joined this forum today although ive had my RX8 over 2 years now. Ive been having misfire problems the last few days. Got it ont

Sorry, got it on a diagnostic computer today and it came back as random misfire. Mechanic basically said its trial and error, and suggested the coils first (like everyone else always says lol). Anyway i drove the car 8 miles home from the garage down the motorway. Limp mode kicked in with a misfire, my cat then got destroyed and sparks all over the road. Pulled over and called the recovery man. After an hour and a half of waiting he turned up started the engine and suggested i drive with him following me. So we did this, and guess what? No more cat no more misfire. Drove brilliant for the short drive home down the motorway. As it was the most expensive thing to change it was going to be last on my list. Im goin to give it a short drive again without the car to makesure it wasnt just luck, but the shape of the hole in the cat suggests there was a puddle of fuel thats burned right through. Its been flooded twice since ive had it. I know this is an old thread but the red glowing cat you describe is exactly how mine just looked, until its disolved infront of my eyes. Has your issue been sorted and if so what was the problem?

my car was having a similar issue. just took a bit longer than normal cranking to start. a trip to the dealership told me that the issue was the starter and it was a mazda recommendation to upgrade to a newer unit that had a higher rpm that mazda produced after so many cars having this problem.