Injection Timing: Adjusting

Shut off engine. Note relative position of marks on pump flange and pump adapter. Loosen nuts or bolts retaining pump to the adapter. Rotate pump to left to advance timing and to right to retard timing.
On V8 engine, width of mark on adapter is equal to about 1°. On V6 engine, width of mark on intermediate adapter is about 2/3°.
Adjust timing. Tighten pump nuts to 18 ft. lbs. (24 N.m) on V8 engine. Tighten bolts on V6 engine to 35 ft. lbs. (47 N.m).
Start engine and recheck timing. Reset timing if necessary. Adjust pump rod on V8 engine. On V8 and V6 engines, reset fast and curb idle speeds. See appropriate article in the TUNE-UP Section.
NOTE: Wild needle fluctuations on timing meter indicate a cylinder that is not firing properly. Condition must be corrected prior to adjusting timing.
If after resetting timing, timing marks are far apart and engine does not perform correctly, dynamic timing still could be incorrect. A malfunctioning cylinder can cause incorrect timing.
If so, check timing on alternate cylinder. Timing can be checked on cylinders No. 2 or No. 3 on V8 engine or, No. 1 or 4 on a V6 engine. If timing difference exists between cylinders, try both positions to determine which timing works best.