I have an 86 LG-4 Trans Am. I have a problem with major spark knock on the expressway. I put a new knock sensor in,and set the timing to 0 deg. I tried retarding the timing with no diffrence. it seems that there s little to no spark knock under daily driving but it is very prevolent when you load the car up like accelorating to get on the freeway. if you get on it the spark knock actualy subsides a bit. Could it be a lack of fuel? ESC module? any suggestion would be greatly appretiated. I love the car but have put over $1,500 in this thing in the three month's I have owned her ( new radiator,water pump, brakes,knock,coolent,temp sensors,thermastat). by the way the only code's stored are 12 and 41 from disconecting the 4 wire connector at the dist. for timing. please help, i dont want to blow the motor on this 50,000 mile beauty.