lets start with it started loping ran ids and ran test and injector number 1 popped up. i replaced it and it stopped for a while and started back up ran test and it showed number 8 and 1 just replaced number 1. i know number 8 can throw off number one so ran test again and never showed back up been running test everyday for 2 weeks and nothing shows up injector pressure read 450 psi and no codes show up its been killing me trying to find out what is the problem anybodys input would be amazing and relieve so much stress.. i heard it can be so many things just need some help need to know where to begin and what to test and how thanks for your time