If you have access to Insite, problems like that are usually diagnosed pretty well on a road test. First let unit sit overnight key on and connect to Insite. Use Data/Monitor Logger to view all parameters. All pressure sensors (Relative) should be reading 0, all pressure sensors (Absolute) should be reading whatever atmosphere is in your area here at sea level roughly 30"Hg, and all temperature sensors should be reading ambient air temp. I like starting off with this as a baseline when it comes to performance related issues. After that I'd connect 2 fuel gauges (manual) 1 right before fuel pump (last point of suction) and 1 for pump pressure. Then take unit on road test while monitoring gauges and Insite. Never take dash gauges readings as correct, always use manual gauge. Also on N14 where the fuel line goes up in to the top left side (If memory serves me correct) of the ECM cooling plate, if you disconnect the fuel line, get some pliers and gently pull on the male fitting in a twisting motion, the tapered tip wil pull out and behind it will be a spring, sometimes itll get backed up with trash causing a restriction.
My 2000 fld is doing the exact same thing. I had the barometric pressure sensor replaced with no luck
What codes are being displayed when you use the diagnostic mode? This is needed to help you better. I eventually replaced the injector harness. 3 of the sensor/sending kept throwing intermittent codes. I thought as old as my truck is, it would be cheaper in the long run to replace harness than fix the breaks in the wires that I can't see. Most of the mechanics that help on here, suggest the ground wires need checked for good contact. I'm not a mechanic, I only work on my truck. I start to sweat and get goose bumps when the yellow check engine light comes on. I fear the red shut off engine light. Good luck.
Your picture is from a laptop? I mean the code the truck dash gives you. This is key on to start, don't push starter button. This is after you hear the start up cycle. This is the switch for diagnostic. Bottom toggle switch very left side bottom of dash. The yellow CEL and Red SEL flash to give you a code. These pictures aren't in order. I hope you can understand the procedure. Search for "Cummins n14 code" you'll find a table for the flash codes. You changed the barometric pressure sensor and it still codes as bad?
Actually the mechanic pulled the barometric sensor and I guess it went from inactive to active so he told me that that sensor was good and maybe the wire from the manifold pressure sensor to the ecm has a short. But looking at the computer that he was diagnosing with I think I need the barometric pressure sensor
I think there are 3 sensors that connect using the same power feed as the barometric sensor. Any of those 3 go bad and the ECM can be confused about which one is bad or has a bad connection. Use the search box top right of this web page, N14 injector harness, this will give you a lot of reading material. Good Luck
