Black soot
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 3,194
Likes: 27
From: Monroe Twp, NJ
Black soot
My 84 was set up by the last owner with a Xram high performance manifold and all the smog equipment removed including EGR valve and air pump and tubes and the Catalytic converter. The car runs fantastic but after even short trips black soot is always seen on the rear tail of the car. The cars computer has also been removed and been replaced with a computer from a newer Camaro.The car does not smoke or leave black smoke when stepped on. Any idea where the soot is coming from?
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 3,194
Likes: 27
From: Monroe Twp, NJ
Plugs are fine and it uses about a qt every 1000 miles. Its got 148K on the clock. I figure with that milage a Qt every 1000K is acceptable? No blue or back smoke coming from the back on WOT.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
Instructor
Joined: Sep 2005
Posts: 146
Likes: 0
From: MN
I'm assuming you didn't have this problem before your changes. Make sure your o2 sensor is functioning properly and check for exhaust leaks upstream from the sensor as this will fool the 'puter into thinking the car is running lean and add more gas.
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
I have the same soot problem and its basically right above the tailpipes. The car uses a quart about every 500 or so. The only time there is any smoke is a little bit at WOT. I have been told I need new valve seals. You may have the same issue.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
Usually smoke at WOT means bad rings. Bad valve seals usually show up as smoke during high vacuum situations such as deceleration. Sometimes during startup a puff of smoke will be emitted.
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