i took out the trailing plug on the rear rotor, and the face of the plug is completely black, what should i look for to see if my plug is actually fouled or not. I DO realize it is in the combustion chamber 100% of the time, so i expect black...my bro says otherwise..

jeff

 

The blackness is from running rich. You can thank your big *** fuel pump for that. A fouled plug will be wet with fuel or oil most of the time.

 

yeah, the plug is less than a month old...damn fuel pump. Im trying to figure out why my idle is rough enough to shake my car (even i cant shake the car if i try because of my shocks/springs). I also get severe amounts of backfire, and bucking at higher RPM sometimes while under heavy throttle. ive been running her really lightly lately so i dont provoke more problems to arise. idling DOES even out when A/C is on though.

haha, that walbro is in my drawer and aint coming out till its absolutely needed.

 

best i could get w/ a flat plug...

 

Those actually don't look TOO bad. Take a wire brush to them, I use a wire brush on a table grinder, cleans'em up nicely, not as good as new, but if there new plugs and you don't want to buy new ones yet, then go for it. Your O2 sensor might be bad...when its no longer functioning the computer goes into pre-mapped fuel mode, where it always runs rich to be on the safe side. It will cause your car to run a little rough and backfire more, but won't actually hurt your car if its not working. Most race prepped FC's don't run with O2 sensors.

 

Yeah, that plug doesn't look that bad. I've seen FD plugs COATED with gas/oil.

 

so i should pull out my O2 sensor on my exhaust? Disconnect the sensor at the harness? check the ECU codes? 'run a little rough and backfire more' is exactly what it sounds like.

gimme some info...

 

if you pull your O2, you going to run RICHER, damn boy, didnt you read "SpeedRacer's" post at all? check your O2 sensor, or replace it if its been a while,hhmm.. just go through and pretty much tune your car up. I agree with them on your plugs arent really too bad at all.

 

One thing you dont want to do to a rotary is drive it easy. That promotes carbon build up that can break off and wedge between the rotor and housing causing you to lose a seal. Another thing you dont want to do is run too rich ... as this also promost carbon build up. So if I were you, Id get this all sorted out before taking it out anymore.


Maybe its just me .. but I wouldnt want to do anything that could promote blowing a motor