Circuit DescriptionThe electronic control module (ECM) enables the lift pump by sending a signal directly to thelift pump. The ECM fast-duty cycles the lift pump ON and OFF during cranking, and it enablesthe pump once the engine has started. Component LocationThe lift pump is mounted to the engine block on the intake side, toward the rear of the engine. Shop Talk1) The lift pump is turned on for approximately 5 seconds when the keyswitch is first turnedON. With the hood raised, it is possible to hear the lift pump running when the keyswitchis turned ON.2) Loose battery connections can sometimes...

Circuit DescriptionThe engine speed sensor provides engine speed information to the ECM. The sensor must be powered up by +5 VDC to operate. The sensor generates its signals by sensing the movement of target teeth cast into a tone wheel that is mounted to the crankshaft. The tone wheel has 35 teeth and a gap where the 36th tooth would be placed. This missing tooth indicates that cylinder 1 and 6 are at top dead center. Component LocationThe engine speed sensor is located on the intake side of the engine block, at crankshaft level, between cylinders 4 and 5 on...

Circuit DescriptionThe engine speed sensor provides engine speed information to the ECM. The sensor must be powered up by +5 VDC to operate. The sensor generates its signals by sensing the movement of target teeth cast into a tone wheel that is mounted to the crankshaft. The tone wheel has 35 teeth and a gap where the 36th tooth would be placed. This missing tooth indicates that cylinder 1 and 6 are at top dead center. Component LocationThe engine speed sensor is located on the intake side of the engine block, at crankshaft level, between cylinders 4 and 5 on...

Circuit DescriptionThe engine speed sensor provides engine speed information to the engine control module (ECM). The sensor must be powered up by +5 VDC to operate. The sensor generates its signals by sensing the movement of target teeth cast into a tone wheel that is mounted to the crankshaft. The tone wheel has 35 teeth and a gap where the 36th tooth would be placed. This missing tooth indicates that cylinder 1 and 6 are at top dead center. Component LocationThe engine speed sensor is located on the intake side of the engine block, at crankshaft level, between cylinders 4...

Circuit DescriptionThe engine speed sensor provides engine speed information to the engine control module (ECM). The sensor must be powered up by +5 VDC to operate. The sensor generates its signals by sensing the movement of target teeth cast into a tone wheel that is mounted to the crankshaft. The tone wheel has 35 teeth and a gap where the 36th tooth would be placed. This missing tooth indicates that cylinder 1 and 6 are at top dead center. Component LocationThe engine speed sensor is located on the intake side of the engine block, at crankshaft level, between cylinders 4...