P0661 Misfires and what is this?
 

I bought a 2004 RX8 not too long ago. At least in miles. Got the OBD light blinking when I drove is so I parked it until a couple days ago when I got a faulty O2 (Rear) replaced. I'm interested in doing things myself but will admit my talents are electronic not automotive (I swapped an engine once but... I can't say I knew what I was doing) Anyhow. Got the new sensor. life is good. I'm driving around for a little while and it starts blinking again (Misfires) the light stops blinking and stays off for a trip into town. I think the blinking was always when I was dogging it. Slowing down which this car doesn't appear to enjoy. If I was in a gear and had good RPMs all seemed to run well. I don't think downshifting caused it but... Can't be sure. Anyway I got it home parked it (I don't want to blow up the engine) and I checked the OBD and got the expected multiple event (Misfires) and a new one P0661. *New one being as the O2 sensor replacement stopped generating new O2 errors from happening so I think I got one thing fixed.

Anyhow. I'm not being too familiar with whats under the hood I looked in and this was hanging loose and appeared to be capable of falling into the radiator fan. As you can see there is no engine cover (What did he do with it? Throw it away?)

I'm pretty sure its for controlling air and maybe the electronic body is?? The source of the P0661 error and perhaps the misfires?

Can anyone please id this thing? I've tried looking at pix of other RX8 but ?? I don't think its part of this after marker air intake but???? And help / suggestions will be greatly appreciated. I would like to do everything myself otherwise I would go to the dealer or? $$ is a bit tight and I have the ol' truck while I tinker.

*Funny part. I asked my neighbor who is something of a car guy to look at this and he noted that the end had a cap/seal on it. He blew into it and remarked at least it seems clear. Then he asked me "Wheres the engine" ha! The size of the rotary engine amazed him.

Well, he you have a cold air intake. I cannot help you with that, but if you had the stock airbox that peice is part of the vacuum for the VFAD. A solenoid connected to an actuator, part of the intake. Anyway, if you are hunting a misfire, read this: SUFFERING FROM A MISFIRE? START HERE.

Not 100% but that looks like the VFAD solenoid, which is part of the original intake system. Since you don't have the original intake system, it doesn't matter, so just make sure it's capped off and not creating a vacuum leak.

As for blinking, 99% of the time it's the ignition coils, and you'll want to replace them, the spark plugs and the spark plug wires before you do any more driving. It's not burning all the fuel and causing further damage.

You guys are great. Thanks I really I appreciate the replies. Wow... No wonder I was confused. This cold air intake is an after market thing. I was really scratching my head watching a video and thinking. Ok, I know I don't have an engine cover so thats different but where is this russian guy finding this big box in the front (Air Cleaner) Duh.... I rate a 9.9 on the stupid meter today.... Well according to the guy I bought her from he spent a bunch of cash to have the engine rebuilt. Apparently that didn't include putting back the bolt holding down the VFAD or the splash guards around the front tires OR THE FRONT OF THE CAR! I have my head shoved in trying to see the Air solenoid and I look at the front to see a couple bolts broken off (Ok shit happens and its a 11 year old car. but.... only one bolt holding the nose of this plane together? What in the..... Someone shoot me.

I'm thinking of getting a spark tester (I know you can run a 6 or 8 cylinder type engine on one less spark plug but??) Or I wonder if there is some type of inline thing?

Misfires are almost always caused by faulty ignition. When was the last time coils/wires/plugs were changed? Those need to be changed as a unit every 25K miles or so. There's a place to start.

You were totally spot on Colon Terminus. Changing the coils and plugs seems to have gotten rid of "random Missfires" Thanks!

P0661 Misfires and what is this?
 

Reading the new owners thread, (and many sticky threads, for that matter) are highly recommended and should be mandatory when signing up (that in itself is a topic for another thread...). Read those to get a deeper understandings of the workings of this car

I know people like to remind everyone to read the entire forum before they ask a question that may have been asked before but God that gets old. I think you can read almost every thread and get the forum police. Believe it or not I did read a ton of posts but the canned info that Coils and Plugs are the problem with misfires is not (Apparently) always the problem. BTW I just finished wasting time reading a detailed thread about P0601 errors which end with someone telling the guy who took a bunch of photos and explained what he did that he was an idiot.

So far. A while back I replaced an O2 sensor that really was bad. The idiot light came on for misfires so I parked it. Just a short time ago (Days) I put in new coils, new plugs (Didn't change wires) and reset the idiot light with a ODB bluetooth program called Torque. Then I bought the full version and got into some mode that showed exactly how many misfires were reported. I drove a little more and the idiot light started blinking again :cussing:So.... the light went out by itself and again it seems like low revs from me driving like an old woman (I've driven mostly trucks or Shitmobiles all of my life) cause the idiot light to blink. Or at least its stop and go traffic that makes it wacky. Anyhow nothing "Stuck" in my half hour trip. The light blinked then it went off. .

Just now I came home from where I was and drove back another 30 minutes and again its blinking but this time its stuck on. Torque tells me rotor number one had exactly 750 miss fires and that P0661 intake manifold tuning valve control circuit low (Bank 1) which is I think what my original post said.

So - I'm wondering if this "combo" of errors indicates something more unique then "When was the last time you changed coils and plugs"

BTW I made the mistake of taking the car into a local garage to have the coils and plugs put in (And told them exactly this) and was told that my idiot light tells them I have misfires and intake manifold tuning valve control low problems but their computer they use to tell them what to do told them the engine blows up routinely so they think I should just pick it up and drive it until it blows up (tough luck) and that will be $59 (or something) for this profound information. This is why I put in the plugs and coils myself and why I am never going to take anything to this particular garage again.

Btw Its raining good and when I came up to the garage the Tach dropped to zero came back to normal dropped to zero then normal. *Engine ran smooth it just looked like someone was flipping a switch on the tach.

I'm feeling really depressed about this car...