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FIX-IT, Technician
Category: Heavy Equipment
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As i have said my N14 Cummins engine idles very high at 8-10rpm

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As i have said my N14 Cummins engine idles very high at 8-10rpm when it get hot, and i notice only when I turn on the ac it comes down to 5-6 rpm. I have tried to use the inc/dec toggle switch but nothing happens. I must say there are other faults that Iam not worried too much about barring this high idle.

Hi there.i can help you with this..


as for the inc/dec switch that will only adjust the rpm by 25 to 50 rpm (very slight) i would suggest making sure the throttle peddle is coming right back to idle..grab it with you hand a make said the vehicle had other faults..what would they be?.is the check engine light on?

Customer: replied 6 years ago.
Foot pedal is ok, engine warning is on flshing, there is a code 115 fault but i dont see this in the code list. I had to unplug the fan and pin it air soloniod look like it gone bad. I runing on MEL minimum equipment list.
Yes,code 115 could definitely be related to your problem,it can make the engine die and run abnormally,it pertains to the engine position sensor is located below the air compressor and just above the oil pump,its a 4 wire sensor,unplug it and inspect for oil.if ok measure the outer 2 wires for resistance and then the inner 2.should be 1000-2000 ohms.if theres oil.automatically replace...hope this helps
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Customer: replied 6 years ago.
It is strange I have run this truck over a year now with this fault and it has never shut down, and remember my major problem is the high idle 8-10 rpm
I understand that you have the rpm problem,but if this code is active,or intermittantly becomes active,we have to address this before going any this sensor is what the ecm uses to reference engine position and rpm..
Customer: replied 6 years ago.
OK then thanks alot when I get back to Jamaica I will do the sensor test you instructed and take from there, threfore I will need a ohm testing tool and also walk with a spare sensor

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