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DR.Cummins
DR.Cummins, FIELD SERVICE TECHNICIAN
Category: Heavy Equipment
Satisfied Customers: 3541
Experience:  16 Years working on Cummins Diesel engines,
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What is a fault code 121 on a 1995 Peterbuilt with an N14 celect

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what is a fault code 121 on a 1995 Peterbuilt with an N14 celect
Hi there.i can help you with this..toss me your engine serial # XXXXX ill have a look..
Customer: replied 6 years ago.
the best I can tell on the engine serial number is SCE855EJDASW
hello this fault is for the ENGINE POSITION SENSOR No engine speed signal detected at one pair of pins, either pins 1 and 15 or pins 11 and 14 of sensor harness The sensor is located in the gear housing behind the accy drive / air comp.
DR.Cummins, FIELD SERVICE TECHNICIAN
Category: Heavy Equipment
Satisfied Customers: 3541
Experience: 16 Years working on Cummins Diesel engines,
DR.Cummins and other Heavy Equipment Specialists are ready to help you
Customer: replied 6 years ago.
THIS ENGINE WILL RUN FINE FOR A WHILE THEN IT WILL START POPPING AND CRACKING
Yes that is the engine position sensor causing the problem remove the sensor check the face of the sensor and check for oil intrusion with in the harness. This is common for these engines
DR.Cummins, FIELD SERVICE TECHNICIAN
Category: Heavy Equipment
Satisfied Customers: 3541
Experience: 16 Years working on Cummins Diesel engines,
DR.Cummins and other Heavy Equipment Specialists are ready to help you
Customer: replied 6 years ago.
OK I am getting ready to try this
Customer: replied 6 years ago.
THANKS FOR THE GREAT ANSWER!!!!!!!!!! IT WORKED!!!!!!!!!
Thanks that is what i am here for. Please leave feed back as i will do the same for you. Have a great weekend
Customer: replied 6 years ago.
i HAVE TRIED TO ACCEPT YOUR ANSWER BUT IT IS NOT SEEMING TO LET ME
Thats ok i see the question has been closed. Glad to help i'm always here.

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