I have a 1988 Buick Park Ave with a 3.8 v6,It cranks over but wont start,before I would unplug the TPS and it would start,now it wont,I checked for fuel and its getting fuel,Ichecked for voltage at the injectors and there is voltage,and i checked for voltage at the ignition module and its getting voltage,but the spark seems to be weak,What do you think this would be?