A weak or erratic signal may be caused by a failing sensor, or it may be due to the relationship between the sensor and the signal notches. There’s not much that can be done with the position of the CMP inside the distributor, but the CKP may not be mounted as close to the flywheel the movie as required to output a consistent signal. Make sure it’s been mounted properly, using the specially machined mounting bolts, but resist the temptation to modify the mounting area or the sensor to move the sensor closer. A properly positioned sensor should work just fine.

The flexplate itself may be damaged. Flexplates on these vehicles have been known to break around the mounting bolts. A flexplate with a broken center section may allow the outer section to shift in and out of position, depending on engine load. Accelerating the vehicle briskly may produce a misfire caused by the broken flexplate and the sensor synchronization problem it causes. You should be able to see the damaged area by unbolting the torque converter and shifting it rearward. A borescope would come in handy here.

Ignition timing is not adjustable on this engine. There’s a procedure for installing the distributor, and a locating peg on the block keeps you from rotating the distributor housing once it’s been properly installed. The procedure involves rotating the crankshaft until the engine is at TDC. The position of the slot in the oil pump gear should be just slightly. If not, a flat-blade screwdriver can be inserted into the oil pump gear to rotate it into the proper position.

An indexing hole in the distributor is used in combination with a locater pin to properly position the distributor shaft before it’s installed. The same distributor housing is used for both 4- and 6-cylinder engines, so indexing holes for both are present. The distributor is correctly installed when the rotor is pointed.

Some advocate grinding the peg off the block to allow a certain amount of manual timing adjustment to bring the sensors back into the synchronization window. If there’s an ignition timing and ring and pinion gear sensor synchronization problem, the underlying cause must be found, rather than attempting a Band-Aid fix.