I had created a thread a while back asking for help about my starting issues and low power and all that jazz. CAT ended up being clogged and plugs were horrible. I mean horrible. I did a seafoam job twice, put new plugs in, and gutted the CAT. When i tell you, the car drove like it just came off the lot brand new. It pulled real hard, smooth revving straight through to 9K, better gas mileage, etc. Low end torque returned too (as much as it comes with lol). Whe i did the seafoam i followed the right procedure, including sucking in a bunch of oil for lubrication before starting it up. Tons of white smoke, stunk...the usual. Ran amazing afterwards. And i have the BHR ignition which was put in 30K miles ago so im sure the coils are good.

Before i did this work i put a new clutch in. The old one went. Bought the suff from BHR as well (i love them). 1 week later the pedal assembly went. Yea...one thing after the other. The shitty welds broke. I didnt even get a warning (that clicking noise) and on my way to work the pedal went sideways. Got to work and drove it home after work with rev matching. That was fun

Bought the reinforced pedal from BHR and this thing rocks. So solid, great spring, love it. Ran great for 3 days until i had the weekend off. I decided to clean my AEM intake filter.

At one point during the seafoaming i found that the shop by me put too much oil in during an oil change (first time brining it there i was strapped for time and couldnt do it myself) and i had oil backfeeding into my intake. There was plenty. The intake filter was black at the bottom too. At the time i cleaned the whole pipe except for the filter. Like i said, the car ran great regardless...like it didnt make a difference.

Fast forward to 3 days ago. I took off the filter and cleaned it. I scrubbed it good. That thing was FILTHY from this winter and past fall. By the time i was done with it i could see light coming through. I used a gas powered leaf blower to dry it and a powered heat source. That was super dry by the time i was done. It almost looked brand new again.

I put the filter back on, cleaned the MAF with the MAF Cleaner, and reset my ESP sensor for timing (i dunno why just seemed like the thing to do).

Turned the car on and it ran like ****. I got more blue smoke from oil burning, the car idled like **** despite it not stalling, and i got misfires above 6K occasionally. When driving it i feel a power loss around 4500rpms and then over 6500 it bogs...like almost completely. Like it hits a wall..stutters, and then gets passed it. It is very sluggish above 6500 and then when it hits 8K it just stops there. It wont go past 8K.

I dont understand this. It was running fine beforehand besides needing a new starter (that's another issue). It drove fine. It drove great. All i did was clean the filter and the MAF...and reset that sensor. After a day of driving like that i did another reset of everything, ECU and ESP, hoping it would solve the problem and it didnt.

ANy idea guys? Im thinking maybe the MAF is the issue? I duno.... Maybe the oil in the intake was causing the SSV to stick or maybe throttle body valve/flap is sticking...but it shouldnt be since nothing has changed.

Im so out of ideas. Ive already put $2K into this car in the last 2 months.

 

It does sound like a MAF problem. Try cleaning the MAF again gently and reinstalling. Clean the MAF connectors. Try swapping MAFs with someone else briefly. Did you forget a vacuum line? etc..

 

Clean the MAF, do the 20 brake pedal stomp, start it up and if it idles let it run for around 15 mins... that is all I got...

 

I have a neighbor with an RX8 (he loved mine and bought one) so ill borrow his and give it a try. I have all vacuum lines hooked up...triple checked that. And the exhaust smells rich too...

One thing i want to note...and this is something that happens very seldom and only during extremely cold temps. When cold starting below 20F degrees, sometimes the idle goes crazy while it warms up. Itll drop a bit and then rocket up to 2500, then down to 1500, then up to 2500, etc. It keeps quickly trying to correct itself until the engine warms up a bit and it settles. It's weird. I dunno if that is somehow related, figured id mention it.

Anyway, i will clean the MAF again, is problem persists ill borrow the other MAF and try that one. Then i guess ill clean the ESP sensor and reset that too, as well as KAM and NVRAM. Ill be back with hopefully good news.

I do feel better though knowing that after all the work i did with seafoam and ignition that the engine ran like brand new. Hopefully that means no compression issues.

 

The idle being wierd at really low temps is normal for RX-8s.

Exhaust being really rich fits with a MAF problem. If you unplug the MAF completely you should get the same list of symptoms, only capping you around 3,500-4,000rpm. (Been there, did that, accidentically)

 

Yea ive done that accidentally too. Except right now she idles...just idles like ****. Rough idling to be precise and it tries to correct itself...drops low to around 500 half the time when at a red light. When disconnected it should not idle at all. At least mine didnt when i left it disconnected accidentally. It goes to idle and then just shuts off.

 

If your idle is "hunting" up and down from normal to 1300 ish...you may have a clutch position switch issue. It is common when replacing the pedal that the switch can be broken.

 

Interesting... is this the same switch that enables the car to turn on when the pedal is depressed?

Also... the car runs great on the low end. That's how ive been able to get around. I get no issues as long as im not idling and when im not above 4500-5500 rpms. Full throttle is where it gets issues as well.

 

The clutch has 2 sensors on it, one to detect full up, the other to detect full down. One of them is the clutch interlock switch to allow the car to start, the other is in the neutral switch circuit since clutch-in is the same as neutral as far as the ECU is concerned.

A neutral switch problem will result in a predictable idle hunt when in neutral, where the idle will jump to around 1,300rpm and then drop back to normal, and repeat perpetually, to the same RPM each time.

What you have described doesn't seem to fit this, since it does NOT cause idle droop at all, and it will not cause any problems with power delivery or AFRs (running crazy rich, which is what is capping your RPM at the moment).

 

Thank you RIWWP. Im at work now so when i get home im going to give some things a try. I am off tomorrow so i can focus on fixing this tomorrow if it isnt resolved tonight. Ill park the car in the garage and watch the snow come down since we are getting blasted lol.