I don't drive my '89 200 much anymore and I notice the other day while hard on the gas a dusty-blackish soot coming out the back... at first I thought it was just dust from the street but then followed the better half later that day and saw for myself that it was coming out of the exhaust pipe.
It will only do it at high RPM under full throttle (1.4 bar) yet if the engine has been running for a while it doesn't seem to be there. Matter of fact today after a 100 mile run to San Diego, I took off from a toll booth, full throttle up to max RPM (1.4 bar) and it was clean with no visible signs of the soot.... Any idea's on what this could be and where to start?
SO.. I replaced the original rear muffler and catalyst converter about four months ago, the middle muffler is still original (parts were not available and I haven't had time to have that one replaced plus it is still in good condition) and I replaced the O2 sensor late last year. Also sometimes I get a really dusty smell from the exhaust as well as a sulfur smell every so often... it was there before/after the catalyst swap. My thinking is the middle muffler, at 15 years old could that be producing the dusty black soot at higher RPM's?
Oh and earlier this year when it was cold and the car was warming up, it would leave a wet black mark on the concrete that came from the exhaust. it wasn't oil or oily, just black like it was wet soot.
Thanks for any advice as always :)
-- Taylor
'89 Audi 200 '03 Audi S6 Avant '98 Jeep Cherokee Sport