If you are having a problem with rough idle, more smoke than normal, "missing" at idle (or low speeds) that's a good sign you need some injector work.

I have a vehicle that had every thing rebuilt (Motor, Trans, Differential) before I purchased it but they reused the old injectors (Makes NO sense at all!) Yellow "rebuild" paint on all the fasteners and on the IP (Which was rebuilt) but nothing on the injectors and nothing on the rebuild sheet.

I started having some pretty bad idling problems. Narrowed it down to the #4 injector. Bought some "good" used injectors off e-bay. Replaced #4 and she ran great...for two months.

I've rebuilt two of the injectors and will be finished with rebuilding the other two this weekend.

Pop-Testing is the way to go, although I've heard from some "old timers" that spray pattern is more important than the actual pressure (assuming injectors are in, or close to spec and close to one another)

__________________
1982 240
460,000 miles total
140,000 on Rebuild