G424F(FE) Service Manual
239
Chapter 8. Basic Troubleshooting
Backfire
Fuel ignites in intake manifold or in exhaust system, making loud popping noise.
PRELIMINARY CHECKS
Perform the visual checks as described at start of “ Basic Troubleshooting” chapter.
Simulate condition by reviewing operation procedure practiced by vehicle operator.
PROBABLE CAUSE
CORRECTIVE ACTION
Fuel system
malfunction
Perform fuel system diagnosis check:
•
Check for fuel leaks
•
Check for MIL faults
•
Check for damaged components
Ignition system
malfunction
Check proper ignition coil output voltage with spark tester.
Check spark plugs. Remove spark plugs, check for wet plugs, cracks, wear,
improper gap, burned electrodes, or heavy deposits. Repair or replace as
necessary.
Check spark plug wires for crossfire; also inspect distributor cap, spark plug
wires, and proper routing of plug wires.
Check ignition timing. Refer to application manual.
Engine mechanical
Check compression: look for sticking or leaking valves.
Check intake and exhaust manifold for casting flash and gasket
misalignment.
Refer to Chapter 3 Engine Mechanical System.
Related MIL Faults:
EST faults / ETC faults / Encoder error
Pre-catalyst O2 sensor faults
Dieseling, Run-on
Engine continues to run after key is turned “OFF,“ but runs very roughly. If engine runs smoothly, check
ignition switch and adjustment.
PRELIMINARY CHECKS
Perform the visual checks as described at start of “ Basic Troubleshooting” chapter.
PROBABLE CAUSE
CORRECTIVE ACTION
Fuel system
malfunction
Check for fuel leaks or leaking injector.
Ignition switching
Make sure power to system is shut off when key is in OFF position.
Fuel lock off valve
Make sure lock off valve is closing properly.
Ignition system malfunction
Check spark advance at idle.
Related MIL Faults:
EST faults / ETC faults / Pre-catalyst O2 sensor faults
Summary of Contents for D20G
Page 2: ......
Page 5: ...Specifications TORQUE SPECIFICATIONS SB2004E00 D e c 1 9 9 8 ...
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Page 138: ...Diesel Engine Engine System 124 NOTE The crankshaft must rotate freely by hand 02900058 ...
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Page 341: ...4TNV98 4TNE98 Diesel Engine Section 3 Engine 87 4TNE98 Engine Figure 6 1 ...
Page 423: ...4TNV98 4TNE98 Diesel Engine Section 4 Fuel System 169 Fuel System Components Figure 7 1 ...
Page 477: ...4TNV98 4TNE98 Diesel Engine Section 7 Starter Motor 223 Starter Motor Troubleshooting ...
Page 494: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 240 Troubleshooting Charts ...
Page 495: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 241 ...
Page 496: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 242 ...
Page 498: ...4TNV98 4TNE98 Diesel Engine Section 8 Troubleshooting 244 4TNE98 Engine ...
Page 499: ...Service Manual G424FE LP Engine G424F LP Gasoline Engine G20G G25G G30G SB4320E00 Jan 2008 ...
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Page 529: ...G424F FE Service Manual Chapter 2 Recommended Maintenance 29 ...
Page 534: ...G424F FE Service Manual Chapter 3 Engine Mechanical System 34 MAIN BEARINGS 0 50 UNDERSIZE ...
Page 584: ...G424F FE Service Manual Chapter 3 Engine Mechanical System 84 ...
Page 729: ...G424F FE Service Manual 229 Chapter 8 Basic Troubleshooting ...
Page 731: ...G424F FE Service Manual 231 Chapter 8 Basic Troubleshooting ...
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Page 820: ...Power Train System Operation 14 Hydraulic System ...
Page 822: ...Power Train System Operation 16 Hydraulic System ...
Page 824: ...Power Train System Operation 18 Hydraulic System ...
Page 826: ...Power Train System Operation 20 Hydraulic System ...
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Page 1023: ...A374081 01 ELECTRIC SCHEMATIC MODEL D20 25 30G EM0K2 EM0K3 Cummins B3 3 ...
Page 1024: ...A654030 00 ELECTRIC SCHEMATIC MODEL D20 25 30G EM0QM EM0QN Yanmar 4TNE98 Tier 3 ...
Page 1025: ...A604500 00 ELECTRIC SCHEMATIC MODEL G20 25 30G EM0QF EM0QG GM G424F Non Certi LP ...
Page 1026: ...A604510 00 ELECTRIC SCHEMATIC MODEL G20 25 30G EM0QH EM0QJ GM G424F Non Certi GAS ...
Page 1027: ...A604516 00 ELECTRIC SCHEMATIC MODEL G20 25 30G EM0QY EM0QZ GM G424FE Tier 3 LP ...
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Page 1059: ...Safety Section 29 Lean away from the direction of fall Lean forward ...
Page 1071: ...General Section 41 Typical Example Side Shifter Serial Number If Equipped ...