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when the glow plug light comes on the ECM has detected an engine management fault and stores a fault code. This does not always indicate a glow plug problem as it could be another engine sensor. To pinpoint the problem we will need to have the stored vehicle faults read with a Jag factory tool. You will need to visit your dealer or Jag specialist for a vehicle scan. You can use an OBD II scan tool so I recommend a trip to your local parts store as they should have a scan tool to use. It is very possible we have a problem with the air flow sensor, injector, EGR valve or other engine sensor. Since we also have this fluid leak it very well could be the turbo or plumbing so we will need to have this inspected as well. Let me know.