DDECIV injectors, is it possible to only pull the solenoid?

Yes you can. You need the gasket kit for it though. Detroit PN 05236116

 

I don't do that though. I install a new injector. Why do the job twice if it isn't the solenoid?

 

Solenoid will normally throw a CEL. Mechanical fault will not. Yes they can be changed. Think its torqx, or anti theft torqx screw head.

 

My solenoid was leaking, never threw a code. It was leaking bad. Sometimes the little screws break, or come loose, causing them to leak. If you have to take one of the 3 jakes off, it’s pretty straight forward. No need to reset it after. You can take 2 of the 3 jakes off, and take off 1 rocker. Change injector, and put it all back together without doing an overhead or adjusting jakes. Just make sure the bad injector is at full height. Get the correct height adjustment tool, and check it first, before taking rocker off. Change injector, setting the height correctly. Put it back together. Be sure to keep everything in the same order. Rocker has to go back on the same way, for oiling. Keep bolts in order. Rocker and jake bolts look alike, but are slightly visually different, near the top. Torque rockers evenly till snug. Final torque the ends first. I think it’s 80 or maybe 100 lbs on rockers and 100 on jakes. As long as the heights set correctly on the new injector, good to go, everything else will stay in adjustment.

 

I’m pretty sure it’s 80 and 100. If you have to take a Jake off, it’s simple, only 3 bolts. I think the one odd bolt gets final torqued first. I should have said, after changing injector, and putting rocker back on, lastly set and adjust the injector height. You would need to know which injector is bad, beforehand, and bar engine over till the bad ones at full height. I’ve changed 2 of them that way. Without doing the overhead afterwards. I don’t think solenoid goes bad often, aside from leaking. Injector harness might be bad, if it wasn’t replaced already. If you decide to change injector, there’s a few other things to consider. Mainly draining the head of fuel, or sucking the fuel out of cylinder, while injectors out. If fuel is drained, you may need to pressurize the fuel tanks to get it primed afterwards.

 

If I remember it correctly, the bolts holding down the jakes need to go back in their original location. One bolt has a narrower body and that is how the jake assembly gets its oil feed. Mix them up and the jakes won't get oil properly.

 

Also be sure to blow out the threaded holes in the cylinder head. They're blind holes that fill with oil once you remove the jake bolts.