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RX-7 2nd Gen Specific (1986-92) RX-7 1986-92 Discussion including performance modifications and technical support sections.

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Old 05-20-2009, 06:20 PM   #16
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I confirmed that a large portion of the exhaust smoke I'm seeing is in fact fuel. I think my AFR may be calibrated in-correctly as it reads 11.0 AFR at 2k (in neutral) and it's pouring out grayish smoke like a chimney. At 1.5k it goes away, and the AFR says it's around 12, but comes back (not as prominent) around my 1k idle.






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Old 05-21-2009, 06:48 PM   #17
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So I ended up melting my MAP line... oops. I replaced and plumbed it into a port away from the turbo and took a chisel and bent/capped off the port by the engine. I figure the penlum after the throttle body will see the same vacuum numbers that the original port did, or at least be some what close.

I do not think the bent/capped off port sealed correctly as I'm only getting around 14-15inHg at idle, though I know the car is capable of pulling close to 19inHg at idle. which leads me to believe that there might be a few little vacuum leaks that I can find and fix to eliminate them. The problem is I don't think anyone makes silicon vac caps and all the rubber ones I put on seem to dry out after awhile.

Though since I did relocate the MAP sensor to the new port my smoking problem seems to have vanished for the most part. I still think I may be running richer than I am being told by the AFR but I think that could be because of an exhaust leak from the EBAY special V-Band and the ATP V-Band adapter for the turbo.

Still burning oil, but the large quantities of smoke do not occur. They are however prominent portions of light smoke with a bluish tint that could easily be from the oil injectors or excess oil in the combustion chamber... though nothing to really consider extreme in nature.
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Old 07-01-2010, 11:11 PM   #18
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McMaster has silicon Vac caps
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Old 07-07-2010, 08:10 PM   #19
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Quote:
Originally Posted by FerociousP View Post
McMaster has silicon Vac caps
Wouldn't have mattered and the problem has been taken care of for some time now.

(The turbo and that specific port had maybe 1/2" of clearance at the most)
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Old 07-09-2010, 09:11 PM   #20
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I was thinking about this and I have a couple theories.

Is it possible that the AFR for your rotors is different, that one rotor is running rich and the other lean?

Typically the wideband port favors one rotor exhaust in what it reads (although not true on a turbo).

Does the wideband dance at all? One rotor may not be burning the fuel at all occaisionally, dumping raw fuel out the exhaust. I have seen engines with a weak face smoke white with fuel mist.
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Old 07-10-2010, 05:54 PM   #21
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I fixed this issue. It was the MAP line. Since the line had a large hole in it it was reading WOT which meant that the injectors were dumping fuel into the engine.
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