Repair of Electronic Unit Injector Solenoid and Seals
Perform the following steps for solenoid replacement: ?

Loosen the injector wire terminal screws two turns and remove terminal wires.
Loosen four hex-head screws and remove old solenoid.
Perform the appropriate step for the DDEC unit used. For DDEC I and DDEC II, discard the solenoid, load plate, follower retainer, and screws. Do not reuse old screws. For DDEC III/IV, discard the solenoid, follower retainer, and screws. Do not reuse old screws. The load plate must be reused.
Remove spacer and seals from injector body.
Discard seals, but do not discard spacer.
Install new seal in spacer groove and position spacer on body with seal facing down. Seal may be retained in groove with small quantity of grease.
Install new seal in solenoid groove.
Install solenoid on spacer.
Install new screws through the load plate and follower retainer, solenoid, and spacer.
Thread screws into body and tighten all screws until heads contact retainer and load plate with a slight force (less than 0.6 N · m [5 lb · in.] torque) in the sequence shown.
Torque screws to 2 N · m (19 lb · in.) in the sequence shown.
On DDEC II injectors only, etch the last four digits of injector part number on the load plate.