partsandservice
Senior Member
So I had a Tigercat buncher with a Cummins QSB6.7 tier 3 with a spn157 fmi 18 which translates to rail pressure not reaching command. This particular code can be troublesome at times because the issue could be anywhere from the fuel tank to the injectors. The code would not be active until the engine was throttled, then it would become active even without applying any load. So first I addressed the fuel supply and changed the fuel filters, no change. Next I checked the tightness if the injector tubes. All were somewhat loose with two way too loose. After this I thought the problem was resolved, the code did not set immediately. After 15 minutes or so of operating the machine the same code appeared again. Next I hooked up the TEXA software. At idle the measured rail and commented rail pressure were the same, but upon throttle the command pressure was about 2k higher than measured psi. My next thought was an injector leaking . I then plugged off each injector one at a time. The pressure differential never changed. I noticed with key on engine
off I noticed that measured pressure was negative 500 psi and jumping around . I replaced the rail pressure sensor and the issue was resolved. So all this to say, this TEXA software has opened repair diagnostic capabilities that is necessary to continue to be relevant as an independent off road mechanic.
off I noticed that measured pressure was negative 500 psi and jumping around . I replaced the rail pressure sensor and the issue was resolved. So all this to say, this TEXA software has opened repair diagnostic capabilities that is necessary to continue to be relevant as an independent off road mechanic.