myroad700 Workshop-manual : Page 27

          1. GENERAL INFORMATION                                                                            MYROAD 700i


 ENGINE LACKS POWER

 Inspection/Adjustment                               Symptom                    Probable Cause
 Connect the diagnostic
 tool, then check EMS and
 correct problems.

 Start engine and                                                               Clogged air cleaner
 accelerate lightly for                                                         Clogged exhaust muffler
 observation                                                                    Faulty spark plug
                                                                                Faulty throttle
                                   Engine speed           Engine speed does     Faulty fuel pump
                                   increases              not increase          Faulty fuel injector
                                                          sufficiently          Improper valve timing
 Check ignition timing                                                          Low or no compression


                                    Correct timing          Incorrect timing    Faulty ECU
                                                                                Faulty CPS
 Check valve clearance
                                                                                Improper valve clearance
                                        Correct                  Incorrect      adjustment
                                                                                Worn valve seat (valve stem too
                                                                                protruding
 Test cylinder compression
                                                                                Improper valve and seat contact
                                     Normal                    Abnormal         Worn cylinder and piston rings
                                     compression               compression      Blown cylinder head gasket
                                                                                Flaws in cylinder head
 Check fuel injector for                                                        Improper valve timing
 clogging

                                     Not Clogged                 Clogged        Fouled fuel injector

 Remove spark plug and
 inspect
                                  Plug not fouled or        Plug fouled or      Fouled spark plug
                                  discolored                discolored          Incorrect heat range plug
 Remove oil dipstick and
 check oil level and condition
                                                                                Oil level too high
                                   Correct and not             Incorrect or     Oil level too low
                                   contaminated                contaminated     Oil not changed
 Remove cylinder head
 bolts and inspect
                                 Valve train lubricated   Valve train not       Faulty oil pump
                                 properly                 lubricated properly
                                                                                Insufficient coolant
 Check if engine overheats                                                      Faulty thermostat
                                                                                Worn cylinder and piston rings
                                                                                Mixture too lean
                                   Engine does not          Engine overheats    Poor quality fuel
                                   overheats                                    Excessive carbon buildup in
                                                                                combustion chamber
                                                                                Ignition timing too early
                                                                                Air in cooling system



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