Originally Posted by 05 Pstroker
My first problem started about 1 1/2 years ago. I had a trouble code for #4 injector contribution problem. After reading figured I had an injector going bad. Had a diesel repair company quote around $2000.00 to change #'s 2,4,6 and 8 injectors. So I decided to try the synthetic/Rev-x concoction and seemed to clear it up for a while but did not get back to 15-17 mpg I had been getting. My truck started running rough again this summer so I tried Rev-x again with no change. Truck was still starting rough at lows in the 60's. Then about two months ago both batteries went bad and the condition worsened. Changed batteries no change. Three weeks ago FICM voltage dropped below 44 for the first time and continually got worse going below 36 under high throttle. I was getting a check engine light with injector contribution codes for every injector. Ordered a refurbished FICM from Ed's FICM Repair and installed it last weekend and truck is running with no starting issues, quieter and getting at least 3 more mpg's. My question is would it not be a cheap ($150.00-200.00) troubleshoot to change the FICM first and see if that fixes the injector problem, which I thought I had, rather than spend the money to change injectors first. I have not heard of a way to check the FICM other than when it starts dropping voltage. Or could there still be issues with the injectors? Thanks for any input.
Most of the time, from what you describe, and watching battery, ficm koeo cold, koec cold, and koer cold. You can see the ficm voltage at some point below 46v, it's done. Was you watching the ficm, and battert prior to injector replacement?
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