Operating instructions

Engine speed not steady
Component Probable cause Task
Fuel injection equip‐
ment
Injector defective Replace (→ Page 125).
Speed sensor Defective Contact Service.
ECU Defective Contact Service.
Charge-air temperature too high
Component Probable cause Task
Engine coolant Incorrect engine coolant concentration Check (MTU test kit).
Intercooler Contaminated Contact Service.
Engine room Air-intake temperature too high Check fans and air supply / ventilation
ducts.
Charge-air pressure too low
Component Probable cause Task
Air supply Air filter clogged Check signal ring position of service in‐
dicator (→ Page 138).
Intercooler Contaminated Contact Service.
Exhaust turbocharger Defective Contact Service.
Coolant leaks on intercooler
Component Probable cause Task
Intercooler Leaking, major coolant discharge Contact Service.
Exhaust gas black
Component Probable cause Task
Air supply Air filter clogged Check signal ring position of service in‐
dicator (→ Page 138).
Fuel injection equip‐
ment
Injector defective Replace (→ Page 125).
Engine Overload Contact Service.
Exhaust gas blue
Component Probable cause Task
Engine oil Too much oil in engine Drain engine oil (→ Page 141).
Oil separator or oil preseparator of
crankcase breather clogged
Replace.
Exhaust turbocharg‐
er, cylinder head, pis‐
ton rings, cylinder lin‐
er
Defective Contact Service.
MS150047/02E 2012-03 | Troubleshooting | 83
TIM-ID: 0000010521 - 001