Polaris RZR XP Service Manual page 419

12. Check ECU and connections.
• ECU could be faulty causing concern.
• Check ECU for power and grounds to make sure that
computer is turning on.
13. If all previous checks pass, concern may be caused
by internal engine issue.
• Refer to Cylinder Leakdown Test.
• Previous testing may be caused by or lead to
replacement of one or more of the following:
– Cylinder head gasket leak
– No valve clearance (cam wear)
– Cylinder or piston worn
– Piston rings worn, leaking, broken, or sticking
– Bent valve or stuck valve
– Valve spring broken or weak
– Valve not seating properly (bent or carbon
accumulated on sealing surface)
– Rocker arm sticking
9929419 R02 - 2018-2019 RZR XP / XP 4 Turbo S Service Manual
© Copyright Polaris Industries Inc.
DIAGNOSTIC
10
10.9