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.060 restrictor installed, proper crankcase ventilation, weird idle...

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Old Sep 20, 2007 | 02:12 PM
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.060 restrictor installed, proper crankcase ventilation, weird idle...

I have installed a .060 restrictor in my turbo oil feed line and ventialted the crankcase properly. My smoking turbo problem is GONE, but I have a weird idle. I think it has to do with my AFR. I know that this may not be totally accurate, but I have an Apexi turbo timer w/ AFR reading. When I let my car warm up the AFR is anywhere from 12.0-14.6 and after letting it idle for longer it shows anywhere from 16.0-20.0 - This means too much fuel correct?
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Old Sep 20, 2007 | 02:15 PM
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at idle your reading will not be correct... the cars computer will try and compensate at idle causing your afr gauge (especially if it is a narrow band) to be innaccurate. depress the pedal for a moment and hold it there (5-10 seconds at 2k or so and read your afr
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Old Sep 20, 2007 | 02:19 PM
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The AFR is Air:Fuel ratio, so the higher the number gets (14, 16, etc) the leaner its running NOT richer. 14 (AIR) : 1 (FUEL)
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Old Sep 20, 2007 | 09:24 PM
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Originally Posted by SpooledupRacing
athe cars computer will try and compensate at idle causing your afr gauge (especially if it is a narrow band) to be innaccurate.
Wrong about the stock ECU trying to adjust AFR's at idle.
It's not a closed-loop system at idle.

You're right about the narrow-band O2 sensor not being accurate though...


-Ted
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Old Sep 22, 2007 | 02:56 AM
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I know... I know... the narrow-band isn't the most accurate way to check my AFR, but I figured it would give me an idea.

Thanks YaNi, that makes more sense to me now... I have a BNR stage 4, cone filter intake, RB exhaust, Walbro, and RTek 1.8 with only 720cc primaries and secondaries. Would it make sense to get bigger injectors then?
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Old Aug 7, 2008 | 06:26 AM
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From: ct
do you have a pic or diagram of your restrictor and how you routed your crankcase
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Old Aug 7, 2008 | 09:15 AM
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check for vacuum leaks.
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Old Aug 7, 2008 | 09:28 AM
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Originally Posted by SpooledupRacing
at idle your reading will not be correct... the cars computer will try and compensate at idle causing your afr gauge (especially if it is a narrow band) to be innaccurate. depress the pedal for a moment and hold it there (5-10 seconds at 2k or so and read your afr
That's incorrect. The only time the stock ECU runs under closed loop is light load cruise. At idle and everywhere else, it's open loop.

If the emissions system is in tact, air is being pumped into the exhaust manifold at idle causing an off-the scale lean condition.

Additionally, the stock O2 sensor cools down too much at idle and will not read correctly.
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Old Aug 7, 2008 | 01:02 PM
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From: https://www2.mazda.com/en/100th/
Originally Posted by Aaron Cake
That's incorrect. The only time the stock ECU runs under closed loop is light load cruise. At idle and everywhere else, it's open loop.

If the emissions system is in tact, air is being pumped into the exhaust manifold at idle causing an off-the scale lean condition.

Additionally, the stock O2 sensor cools down too much at idle and will not read correctly.
i put a wideband on a stock s5, and it was reading 16-18:1 at idle. under light load low rpm, i saw as lean as 20:1
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Old Aug 7, 2008 | 01:06 PM
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Off the scale lean on a narrowband.
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Old Aug 7, 2008 | 01:51 PM
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I would check the tps for proper adjustment. Alot of the time thats the problem.
Thanks Robert
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Old Aug 7, 2008 | 08:22 PM
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From: ct
aaron do you have a diagram how to route the hoses ...for turbo smoking ...what do you do with the purge valve
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Old Aug 7, 2008 | 09:01 PM
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Originally Posted by j9fd3s
i put a wideband on a stock s5, and it was reading 16-18:1 at idle. under light load low rpm, i saw as lean as 20:1

Is this with or without the ACV and airpump working? Personally I've never seen/heard a RX that would idle at those figures, UNLESS the airpump was mixing air to the exhaust ports prior to the 02 sensor (like where else would that happen, duh).

Most all the idle figures I've seen were best at 13.0 afr,give or take a few percentage points, and nothing but skipping, crummy idle above say 14.0 afr. I've used two brands. Zeitronix and TechEdge controllers.

Right now I've a sixport turbo headed for the emissions testing and it's reading around 16.5 afr (idle)with all emissions working. Disconnect the Switching solenoids vacuum to the ACV and it drops down to the 13 afr area (no air to the exhaust ports if that's done).
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Old Aug 8, 2008 | 01:14 PM
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a stock s5 = ACV on. It is well known that rotaries don't idle well above 13.5:1 (undiluted by air pump) at the leanest, and often richer than that depending on porting etc.
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Old Aug 8, 2008 | 01:33 PM
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Originally Posted by dennis blackstone
aaron do you have a diagram how to route the hoses ...for turbo smoking ...what do you do with the purge valve
Stock.

The diagram for both the TII and NA is in the Haynes and FSM. I've always just retained the purge valve nd connected them in a stock form.

However I'm going to simplify my car a bit as follows:

Bottom nipple from oil filler (on center iron) goes to catch can with little air filter on top. Top nipple Ts to the charcoal canister and then connects to a big nipple on the intake via a part store PCV valve.
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Old Aug 8, 2008 | 02:29 PM
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From: https://www2.mazda.com/en/100th/
Originally Posted by HAILERS
Is this with or without the ACV and airpump working? Personally I've never seen/heard a RX that would idle at those figures, UNLESS the airpump was mixing air to the exhaust ports prior to the 02 sensor (like where else would that happen, duh).

Most all the idle figures I've seen were best at 13.0 afr,give or take a few percentage points, and nothing but skipping, crummy idle above say 14.0 afr. I've used two brands. Zeitronix and TechEdge controllers.

Right now I've a sixport turbo headed for the emissions testing and it's reading around 16.5 afr (idle)with all emissions working. Disconnect the Switching solenoids vacuum to the ACV and it drops down to the 13 afr area (no air to the exhaust ports if that's done).
thats with air pump and acv, car is 100% stock, automatic even.

the cat like a slightly rich mixture, if you're a little lean emissions go up. if you lean it out and it misfires then emissions go WAY up.

interestingly the rx8 idles in the 14's and you can kinda tell
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Old Aug 8, 2008 | 03:51 PM
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From: ct
emissions

could you mark the route on this diagram
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Old Aug 8, 2008 | 04:02 PM
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Originally Posted by dwb87
I have installed a .060 restrictor in my turbo oil feed line and ventialted the crankcase properly. My smoking turbo problem is GONE, but I have a weird idle. I think it has to do with my AFR. I know that this may not be totally accurate, but I have an Apexi turbo timer w/ AFR reading. When I let my car warm up the AFR is anywhere from 12.0-14.6 and after letting it idle for longer it shows anywhere from 16.0-20.0 - This means too much fuel correct?
Holy ****, i didnt understand squat, good thing others do...
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Old Aug 10, 2008 | 09:29 PM
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From: ct
crankcase

could mark where you routed your hoses to stop smoking
Attached Thumbnails .060 restrictor installed, proper crankcase ventilation, weird idle...-crankcase-3-routing.jpg  
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