detectiveorange

mod edit: no need to stir the pot weeks later...

Kennedy, best of luck with your car bud. Sorry, members like that just bug me. Trust RIWWPs word, I've never heard bad information from him and if he doesn't know something he'll tell you he doesn't know, not make up bullcrap to make himself look smart.

RIWWP

iTrader: (2)

Sorry I didn't see this, was rather busy with holiday stuff.

Ok, so no vacuum leak, and your fuel trims don't appear to be out of wack.

What app are you using? I can look it up and guide you through it.

kennedy_RX8

It's ok....I forget the app right now it's in another phone. But I did read a misfire code but it didn't identify where at so I think i might just replace the plugs and wires again to see if that helps. I'll let you know what app it is tomorrow. Thanks

kennedy_RX8

The app is the torque app you told me to use the free one. I replaced my plugs and wires cause of the misfire code still didn't fix it. I noticed to that on my rear bumper I'm getting a orange residue and my exhaust smells like straight gasoline and I'm getting poor fuel mileage. Idk of any of this helps but just more stuff I've noticed

RIWWP

iTrader: (2)

The orange residue is oil soot, typical for catless rotaries, nothing to worry about at the moment.

Ok, I'd like you to grab a data log from Torque of this problem.

- Connect to your ECU through Torque
- Pull up the settings menu (how will depend on your phone's buttons, but shouldn't be anything abnormal)
- Tap into Data Logging and Upload
- Tap Select what to log
- Tap the settings key and select "Add PID to log"
- Add each of these:
Air Fuel Ratio(Commanded)
Air Fuel Ratio (Measured)
Engine Load
Engine RPM
Short Term Fuel Trim
Long Term Fuel Trim
Mass Air Flow Rate
and find a Throttle Position PID. There are several, and I'm not sure which one the RX-8 provides data through
- Back out of this list
- Tap to turn on "syncronous logging"
- Uncheck Automatically log GPS

Then go driving. Make sure you can duplicate the problem, and then go into Realtime Information, tap the settings key, and tap "Start logging" Duplicate the problem a couple of times, then tap "Stop logging"

The log will be in the phone's flash memory, send it to me (I'll PM you my email address).

I have a couple ideas, but I'd like to see what is going on with those values

Raistlin

I'm chasing a very similar issue and with all the testing and replacements I've done, I'm down to either a small vacuum leak or the internals are not sealing. Adapter ordered for final round of tests and can provide a ton of info on what I've done and experienced if anyone might be able to offer pointers. Probably best to wait until after Wednesday so I can offer full report on MAF numbers and STFT. Hoping this last test will yield a positive result, but I'm also prepared to order the rebuild kit from Atkins if need be.

I posted all the stuff I've tried on another thread, copied into this one below.

I would love a solution to this issue. I've been dealing with this for some time now and I'm losing it. 2006 6MT and same kinda thing, about 5k RPM and up, a God awful rattling sound like the engine is coming apart at the seams accompanied by power loss. Only happens under load with the engine hot. I have already replaced the SSV, the VDI, the APV valves, and verified the solenoids and APV motor are good. Valves all move freely, even hot (about 7 inches of vacuum applied for full activation). I'm running 91 octane fuel and verified today that the catalyst is fine, both via scanner and physical inspection. All new ignition coils, plus, and wires. Fresh oil. I'm at the point where I can only assume the damned apex seals are leaking compression at high RPM, but I'm really hoping that's not the case. Seems fine at idle and sometimes it'll actually come back to life when hot if it's run hard. No coolant in the oil either. Like I said, I've done everything I can think of and I'm stumped. Hope this is helpful info for any real gurus out there.

Raistlin

RIWWP, you seem incredibly knowledgeable, sir, and I'd love to have your feedback on a similar problem. See post 31 below. Greatly appreciate any help you can offer. (Wouldn't bug ya, but it seems like you're one of the resident RX doctors lol)

RIWWP

iTrader: (2)

Due to the power loss that accompanies the noise, the most likely case here is ping/detonation/knock. Which is bad. Without that power loss, I'd point you to non-engine rattle sources.

If you have better than 91 available anywhere, even if it's race gas, I'd recommend seeing if using that to see if the problem disappears. There is another solution if 91 is the best gasoline you have available, but I don't want to suggest it yet until we know what your AFRs are when the problem is happening. If you are pinging due to going lean, this other suggestion would make that severely worse. If you are pinging due to carbon caking then it would clear up instantly. But I'll wait on that till we know your AFRs.

I recommend that if you have to drive it, keep the revs low and stay out of full throttle. If you can avoid driving it until you get in the OBD2 adapter, then that would be best.

To prime the possibilities though, in order of most likely with the information you provided...

Knock due to fuel pump failure
Knock due to a fuel injector problem
Knock due to carbon caking

Raistlin

That is precisely what I've been doing. Keeping out of high end and WOT as much as possible. Car sees a lot of city driving and based on condition of the APVs, I'd not be surprised to find out its a carbon issue. I should have the adapter tomorrow, can monitor the AFRs and MAF readings on the way home and I'll report back then. If it helps, I did do an induction cleaning with Seafoam and that seemed to make it a tad worse for a day, then right back to the SSDD. In any case, I'll post the numbers up tomorrow and we'll see what we can determine. Thanks again for your help!

Raistlin

OK, so I have 2 data logs attached here for review. The longer one, I was experiencing the power loss/rattle. Most notable occurance was at 21:09:40 to about 21:10:00. Also had it happen distinctly at 21:13:48 to about 21:14:18. For purpose of comparison, I have a second log that I got this afternoon where the car seemed to run fantastic (lots of power, no noise, generally seemed perfect), but idled a tad funny-seemed almost too smooth if that makes sense. One thing I've been noticing....my engine seems to idle a tad high all the time. sitting at about 800-820 RPM fully warmed up and I understand the base idle should be around 760 RPM. Anyhow, please have a look if you are interested. I'm hoping this moves us forward here. Thanks again guys/gals!

RIWWP

iTrader: (2)

You have a vacuum leak.

It's pretty clear in the data. Low MAF at idle, high fuel trims at idle, running leaner than commanded at idle.

Unknown if it is causing your stumbling problem, but until your vacuum leak is fixed it will be a wild goose chase.

Raistlin

Ok, so I took the car in and did the smoke test for vacuum leaks (we have a proper smoke tester where I work). Unfortunately, I found no vacuum leaks. I mean, the thing is sealed up tighter than a frogs butt. Only smoke I had anywhere was a tiny wisp from 2 of the breather lines where the plug into the intake boot (throttle body boot). Replaced the elbows, rechecked, found nothing else after over an hour looking. Little or no change. Is there something I'm missing? I piped the smoke in though the EVAP port at the intake initially, used one of those inflatable deals you insert in the intake boot on the second and third pass. I wonder, though, if the lower injector seals were leaking, would that show in a smoke test?

Raistlin

And the saga continues. Ran compression test today just as a double check, but hard to get a good idea of actual RPM while cranking (at least it is in my garage at home). As near as I can measure, I'm hitting about 62 psi around 125-150 RPM with less than 2 psi of variance between front and rear housings. Sounds like perhaps my vacuum leak is simply worn out internal seals if I'm reading the numbers/charts and estimating my RPM accurately. Which would really not make my day lol. But I'd love your take RIWWP.