My 94' 850 turbo started comming up with the same 1-4-3 Front Knock Sensor code about three months ago. I'd clear the code and it did not come back for about five weeks the first time, now clearing the code lasts about a day or two. Checked the dealer and they offer two replacment parts, one for $98.00 which is two sensors wired to the same plug, (3 pin) and a $78.00 kit which is the same as the $98.00 part plus an adaptor that converts the 3 pin single connector to two 2 pin connectors and an extra bracket and connector shell. I know the book says you need to remove the intake manfold to replace the knock sensors, but I could swear last summer when I replaced the A/C Compressor I could see and get to both of the sensors from underneath. Does any one know if it is really necessary to remove the intake to replace them? I'd rather weld two or three tools together for that "special" than have to mess with pulling the intake.