OM617 Injection pump issues....i think

[sdnewbie]

So this weekend I pulled out my prechambers as they've been leaking for quite some time in the process I noted that two of the injectors (4&5) were out of a 240d. Having spare housings and internals for 300sd injectors I cleaned and replaced everything but the lower cases as they were identical. However my car will not start acts like it almost will and when I tested the injectors out of the engine. I couldn't get the first one to pop. When I tried it on another line it popped just fine. Could my injection pump be bad...or is this a case of injectors needing balanced? Any thoughts on this greatly appreciated. Also to note it was starting fine in 22 degree weather three days before and fired right up the morning before but now it's so so close just never quite fires all the ways