Euri

Ok, I just put in new BHR ignition coil packs, NGK wires and iridium plugs, mass airflow sensor, air filter, and cleaned the throttle...she started up smooth as a dream come true and idles at a smooth 1200 rpm...but she's running so rich it made me dizzy in less than a minute with the garage door open...

The long story...
She's a 2005 (6 spd ofc), I bought her in February and drove her home (little over an hour), no performance issues. She's a second car, not a primary; an impulse buy I found while daydreaming on the internet. I had wanted a blue RX-8 since they came out. I had a black '04 back in the day, but had to leave it in Hawaii when I got out of the Army. My daily is a blue BRZ that I bought because I never got a blue RX-8. The RX-8 is a 'project' car, that I meant to restore cosmetically as I am not a mechanic, and hadn't intended to be. But between YouTube, this forum, and the fact that I don't trust anyone else to touch her, I am firmly on that path.

I drove her to work twice (to show off), 8 miles each way, no issues. Drove it to Winchester Medical 33 miles each way to test run the drive (I'm an RN and considering applying there) and take her for a nice drive. That drive was up a mountain, center console got VERY warm, but engine temp was fine, and again, no performance issues. Drove her to work one more time, and immediately upon starting to come home she was acting weird. First something electrical funky, radio cutting in and out, but she's nearly 20 and has an aftermarket bluetooth-to-aux thing so I can listen to music and take phone calls, as well as an aftermarket back-up camera, and I put LED bulbs in the tail lights (they hyperblink, haven't put in the modulator yet) so a little buggy radio that did connect wasn't the biggest shock in the world. I started to head home and from the first stop sign she had NO power. It was like you were trying to take off from stop in 3rd. I don't live far, only 4-5 stops, and she seemed ok once up to speed so I limped her home. I revved her up a bit whenever I needed to take off from stop, still having power issues but able to go and not overheating. I had already purchased all the above mentioned parts as part of my initial refresher for her, so I put her in the garage and had not attempted to start her again until they were installed. She smelled TERRIBLE on the way home that day; between the smell and the hot console, I was very concerned that she needed a new cat. But she just smelled insanely rich, not like sulfur or any of the other smells described by owners of bad cats, and no discolored smoke. So I figured I'll put in all the parts I already bought and and pray it was an ignition issue. Finished that up tonight. Turned the key, popped right off and purred like a kitten. Before I could even think to get excited, that rich smell hit. I thought maybe she just needed to burn off a flood from the journey home, but it was was so strong I was literally dizzy in less than a minute and had to shut her off.

So I came here, seeking yall's wisdom. Yes, I have done all the research I can because she has smelled rich from the start, but the consensus seems to be 'yea, they run rich.' I have pics of nice black spark plugs I pulled out, but again 'yea, they do that.' I have read the 'new owners start here' thread and many MANY more. I'm working my way through the list advised to replace @60K. I've read enough to know I'm probably going to get several nasty replies for asking dumb questions because haters gonna hate, didn't anyone ever teach you if you can't say something nice don't say anything at all?

I still intend to drop the cat and inspect/replace it. Probably gut it as a temporary fix because I got her inspected right after I bought her and I can get away with it for 2 years if I need to. The more I learn about the RX-8, the more my soul dies for the environment. She is everything 'evil' about cars and I love her still. At least I don't ever intend to make her my primary vehicle long term.

So please, suggestions?

Loki

iTrader: (1)

Normal idle is 800. So idling at 1200 is not great. Is the check engine light on and what are the codes if so? Was there a reason to replace the MAF? Other issues?

Good idea to inspect the cat, it's not living it's best life like this. They don't smell that much once the cat warms up, but cold, any car will smell.

Euri

MAF was replaced because I replaced everything else, why not.

No codes at this time, but I literally only ran it for a minute. I was very concerned about shutting it off cold, but I was quickly becoming concerned that I would pass out before too much longer. I have had the infamous P0420 cat below efficiency threshold, it was my first code and I don't think it re-appeared after I cleared it. I had C1306 when I locked my steering wheel hard over, U2616-19 tire pressure sensors not responding. The last day I drove it home there were several codes - P0506 Idle Control RPM lower than expected, but have cleaned the throttle body when I replaced all the ignition. P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control ??? (I do have a low temp threshold thermostat I ordered but have not installed, ordered before the problem occurred). P0300 Random/Multiple Cylinder Misfire, for which I have done all of the recommended things except clean/replace fuel injectors. C2778 No Code Definition Available (helpful ). And P0076 Intake Valve Control Solenoid Circuit Low Bank 1, no recommendations, also helpful .

Obviously I did not let it run very long this morning, but that day I drove it home it the smell was worst when I got home. SO has complained about it smelling rich the whole time, but it prior to that day it had smelled rich but nothing like this. I could not believe I did not have gas dripping out of the tailpipe or a leak somewhere (there was nothing on the garage floor).

Loki

iTrader: (1)

I wouldn't replace MAFs or other sensors because "why not", depending on who manufactured the replacement, it could create more problems than it solves.

C2778: https://foxed.ca/rx7manual/2003mazda...power%20supply).

Ignoring the C codes for now, the p300, misfire and p0076 seem the most actionable, if they come back after being cleared. Honestly with a history of P0420, the smell and p300, first guess is your cat is dead and is slowing killing your engine. Killed by poor ignition. Did the car drive ok? No loss of power ? Did the CEL flash? At what rpm?

Most of your codes seem to come down to electrical interruptions, so I'd check that your battery terminals are clean and snug. Maybe give the visible grounding points a clean.

Lastly on the idle speed, you're saying it starts at 1200? What does it idle at when warmed up? I would check for vacuum leaks. The intake needs to be airtight after the MAF, including the MAF seat itself. Any extra air will mess with idle. You're looking for cracked hoses, chewed up manifold gaskets, that sort of thing.

It will always smell on startup, even new from the factory. What matters is the smell once warmed up.

Euri

MAF was OEM from Japan, I assume that doesn't matter? The little glass nub thing looked brown and old, not sure if that matters or not, but it wasn't expensive so I replaced it. I'm assuming that anything the original owner (only 1 owner prior to me) only replaced the things that he mentioned, and that everything else is almost 20 years old and wouldn't hurt to replace. I kept the original if you think I should swap it back to see if that makes a difference.

Battery was disconnected for the recent work, reconnected and snugged up very well this morning just before starting it. Didn't clean the terminals, but they looked ok.

It idled at a steady 1200 this morning, but I don't feel like it got warmed up so I can't say if it would have lowered or smelled better if it had. I can start it again and see how it does if you think it's safe to do so. It is backed out of the garage now, so it should be ok for human safety. I'm just scared to do it more harm by driving it.

OF NOTE - the accordion hose is cracked. Apparently I damaged it in the removal/replacement process. The 'warm it up and it will be soft' did not soften it, and I tried with all my arthritic might to get it off on several separate occasions before finally getting it. I have auto-immune arthritis, so I couldn't have pulled it insanely hard, but I did notice a tear at the end that connects to the throttle body. Its not large, and is covered by the hose clamp. I only noticed it because it was able to get it back on the first try. "Well that was way too easy" so I inspected it closely and saw the tear in the 20 year old rubber. Do you think this is contributing? Should I replace that hose? I thought about replacing it when I saw the crack, but that hose OEM was not cheap, so I didn't replace it just for the sake of argument. The tear is small, at the end, and should be occluded by the hose clamp, but if it could be relevant I would replace it. I considered an aftermarket air intake when I saw the tear, but had not yet researched what I would want. Would love to hear your thoughts.

If you think this is an air intake or output (cat) issue, I'm somewhat relieved. Is there any concern about an apex seal? It is the original motor with 61K miles on it, and the power issues the last time it moved more than 5 feet had me very afraid that I might have total compression loss in one rotor. I have not had the compression tested, it's not proving to be logistically simple to do. There is one shop that claims they can do it, but the way the conversation played out did not inspire me with confidence. I'm suspicious that they would charge me $400, use a standard compression tester, and assume I would not know any better. I thought about buying my own, but they seem quite pricey and I do not yet have enough confidence to trust my own results if I were to do so. Thoughts on this?

I still intend to drop the cat and see what's going on back there. I had to get it out of the garage this morning because my boyfriend wants the work space. I should be able to put it back in the garage in a week or so. Do you think I should drive it a little to see how her power is and if she throws anymore codes or wait until I get the cat off? It did have the traction control light on this morning, but not the CEL, but I did not even keep it on long enough to run the ODM2. I could start it and run it in place and check for codes if you think that would be safe.

Loki

iTrader: (1)

I wouldn't drive it under load until you know the state of the cat. If it cat has crumbled, it's restricting exhaust flow, which is extra hard on the seals. Idling shouldn't be a problem especially if it helps diagnose. If you have an endoscope you can always take a look through the rear O2 sensor hole. If the cat has collapsed you might not even need the endoscope :/

I'd replace the accordion hose, or get an AEM or Racing Beat intake, but it doesn't sound like the biggest fire right now. Is that the only crack or is it possible there are others, say on the underside where you can't see it?
So 1200 rpm while warming up is OK, it should settle down to 800-850 once up to operating. If you do get it to a warm idle, have a look at the fuel trims, airflow grams/second and rpm via OBD2. You should see ~5.5 grams/sec at 800 rpm with 0 LTFT and STFT. If you're seeing lower airflow and higher fuel trims, you have a vacuum leak somewhere.

The stability control / power steering light is normal for 1 drive cycle after a battery disconnect, it needs to learn the steering angle sensor before it can promise stability.

You can always try a Mazda dealer for a compression test, the book value for it is something like 1 hour of work, so you can argue if they come back with a $400 quote. Just make sure they actually have a working rotary tester.

Maybe I missed it, did the power loss occur again after ignition replacement, or only before? Because that would be my first guess. Cat failure can cause power loss at high rpm (the more the exhaust is clogged, the lower the rpm where it starts), but it's pretty consistent, doesn't come and go.

Euri

Haven't driven with the new ignition, just backed it out of the garage. I can idle it to warm and run codes if that is safe.

Pretty confident that crack in the end of the accordion hose is the only one, I had it completely off. Would also consider aftermarket air intake. My end goal is to make her run as clean and efficient as possible without impairing her power. Already have a Sohn and an oil catch can I haven't put in yet either.

Figured the traction control was related to the battery disconnect.

The power loss was 100% power to about 50%, with nothing in between, no slow decline. Which made me suspect blown apex seal or clogged cat. There was one moment at the second stop on the way home that day, that she took off at full power ever so briefly, which made me think clogged cat that cleared its obstruction, but then she was right back to 50% power after only a few seconds. Just PRAYING its the cat and not a seal

The only place that even claimed to be able to do a compression test was a Mazda dealership. Maybe the desk guy was just an idiot, but $400 sounded a bit steep and I wasn't buying that it was a rotary compression test at all. Perhaps I will go there in person and see if I get a more reassuring interaction, ask to talk to the mechanic or something. I am very picky about who touches my hair, and my car; but if I trust you I'll pay whatever you ask. (My hair is 100% blue dyed to match my BRZ and isn't cheap!)

I'll fire her up and get you codes and warm idle info. Thanks for all your help.

Euri

Ok started her up, ran full scan, no codes. Except the stupid tire pressure monitors and abs module, so I'm fairly confident I have minor electrical issues.

Let her warm up, and this is strange....cold she idles a smooth 1200. As she warms, the idle lowers to that 800-850 like you said, but its rough. When fully warmed up she idled rough as hell, nearly dying several times, so I shut her off. Then I was like well, lets run the scan again. Warm start was significantly slower than cold start, but didn't really struggle. Ran full scan again, she almost died about 3 times before the scan completed, RPM dropped to like 500 or less and then she would rev to about 1500 and back down again, roughly idling at 800ish. Here's a screen shot of the live data, hope this is what you were needing, my monitoring options didn't match up exactly.



And one more thing, she makes a weird noise if I let off the clutch, even though she wasn't in gear. Not loud, not a vibration or a squeal, I don't know how to describe it. Silences when I push the clutch in again.

Euri

0.7lb/min airflow =5.29 grams/sec so that seems good? Not sure what STFT and LTFT are aside from fuel trims, and not sure what to pull up on my tool to get that information.

Euri

Oh! Did NOT notice a smell! I was in the driveway, not the garage, but I'm sure it would have at least been noticeable as strong as it was in the garage with her *** pointed out the open door.

Loki

iTrader: (1)

Nice the 5.29g/sec MAF rate sounds good if that's at 800-850rpm. All eyes on the cat then

Can you describe the strange sound and is it new? It's normal to hear a kind of marbles slowly rotating in a jar sound when stationary and clutch out, which stops when you clutch it. Peculiarities of the trans input shaft I guess. What you shouldn't hear is screeching or obvious grinding.

Screenshot didn't come through. The idle surging is weird if there's no vacuum leak. A couple of thoughts: clutch safety switch on the pedal could be loose/intermittent, or baro sensor could be messing with the computer. See if jiggling either or disconnecting the baro makes a difference. It's near the air pump on the passenger side of the engine bay.

Euri

Can you see the screenshot now? Rolling marbles seems a fitting description...it's quite possibly always done that because I generally don't operate a vehicle without loud music unless I'm listening for diagnostics. Definitely not loud, grindy, or screechy. I'll try reseating it but I won't get to it until Thursday night. I'm an RN and we work 12 hour shifts +shift change report +charting that we didn't get done during that 12 hours, so I don't do much of anything else on nights I work.