i've been fighting with my car lately with a variety of problems. something's causing the ABS to fail and shut off and something is causing a horrible idle. today i rechecked my wheel speed sensors for metal or debris stuck to the magnet (nothing). a few days ago i found a crack in my exhaust just before the 2 downpipes collect to one pipe under the car (i haven't been able to weld the crack yet). i replaced the overvoltage relay because when the ANITLOCK light flickers on and off the voltage meter spikes and drops wildly and the engine hesitates--no improvement. here's the bad news: i pulled my spark plugs to look at them and found that the ceramic on 3 of the 4 had cracked. trying to solve this idle problem, i just replaced all the plugs about a week ago. at that time i noticed that 2 of the 4 plugs were cracked. also, the two electrodes are clean but the metal portion around the electrodes (the bottom of the threaded part of the plug) was covered in black soot. the plugs are gapped correctly and the wires are in good shape. what does this mean?

please help--my 16v sucks.

thanks

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dew
86' 190e 2.3L 16v