Ok, so I lost an injector #6 about a month or so back. I limped it about 10 miles home being cautious of the egt's and what not. Installed new injector in #6, did a UOA and had a very small amount of fuel contamination. Changed oil and did another UOA about 1500 miles later to check for fuel contamination which came back ok. Now I am 4K miles after this incident and decided to go have an injector contribution check done on my injectors since the other 5 have 125K on them (they are stock). The tech (who works at a local diesel shop) said that my #1 and #6 were down to 89% which he would consider not good on their amount of contribution (the term he used). He is telling me that from here we should do a compression test on the engine, because there may be either some cylinder washdown and lost compression there or I may have the top side losing some compression? What is going on? Anybody have some good advice? I am not ready to think about a rebuild...