Piston Cooling Oil Jet Solenoid Failure | 2.0D Ingenium (Land Rover Models)

Models Affected:

The 2.0 Ingenium diesel engine uses an electronically controlled solenoid to manage oil flow to the piston cooling jets. These jets help keep piston temperatures under control when the engine is under load, reducing stresses and wear on the internals.

However, a common issue on the Ingenium is the failure of the piston cooling oil jet solenoid, usually triggered by coolant leaking from the thermostat housing onto the solenoid body and connector.

This guide covers the symptoms, cause, and correct repair procedure for the piston oil cooling solenoid.

Symptoms of Piston Oil Cooling Jet Solenoid Failure (Ingenium Diesel)

  • Yellow engine management light (EML) on dashboard

  • Critically Low Oil warning message (even when oil level is correct)

  • Diagnostic Trouble Code (DTC): P25A9-00 Piston Cooling Oil Jet Solenoid Control

 

PLEASE NOTE: Do not top up the oil unless the level is actually indicating low on the dipstick. This warning is often falsely triggered by the faulty solenoid unit, and is not an oil level issue.

Diagnosis & Cause

The most common cause of piston oil cooling jet solenoid failure on the 2.0 Ingenium diesel in Land Rover Models is a leak from the thermostat housing gasket, which allows coolant to drip directly onto the piston cooling solenoid. Over time, this damages the solenoid and/or its connector, resulting in a P25A9-00 fault code, the “Critically Low Oil” warning message and the engine management light illuminating.

This issue will not usually put the car into limp mode, but it does need to be addressed quickly to avoid false oil warnings or possible long-term engine damage.

 

How is the problem solved

Access is best achieved from the top of the engine. The job requires removal of several components to reach the solenoid and thermostat.

Step-by-step summary:

  1. Remove the engine cover
  2. Drain the coolant
  3. Remove the fuel filter and housing
  4. Disconnect plastic fuel pipes
  5. Remove all glow plugs
  6. Remove intercooler boost hose
  7. Undo the 10 bolts and remove the inlet manifold
  8. Remove the thermostat unit
  9. Undo the 8mm bolt securing the piston cooling solenoid
  10. Disconnect and carefully prise out the solenoid unit
  11. Fit ac new solenoid and thermostat gasket
  12. Refit all components in reverse order
  13. Refill coolant, bleed system, and clear fault codes with diagnostics
  14. Test drive to confirm permanent fix

The following parts will need to be replaced:

  • LR073684 – Piston Cooling Solenoid Valve
  • LR105592 – Thermostat Seal / Gasket

Estimated Repair Costs

This estimate includes the replacement of the piston cooling solenoid, thermostat gasket, fresh coolant, and labour on the 2.0 Ingenium diesel engine fitted to a second generation Range Rover Evoque. VAT is also included.

Please contact us with your registration for a personalised estimate.

For Ingenium Jaguar Models please see our page here.

Frequently Asked Questions

You can, but we don’t recommend it. While the engine won’t enter limp mode, the “Critically Low Oil” message may continue appearing, making it difficult to know if a genuine oil issue occurs.

In the medium to long term, the pistons may also receive insufficient oil cooling, leading to increased wear on the internals.

No, the failure is electrical and sensor-based. It does not immediately affect oil pressure or engine cooling, but the unit may not function correctly leading to insufficient oil cooling.

Only if the oil is genuinely low. This fault is known to raise false oil level warnings, so always check the dipstick before adding oil.

In most cases, no. If coolant has leaked onto it, the solenoid internals and/or the connector are likely already damaged. Replacement is the only reliable solution.

Need help fixing this issue?

Call us on 01772 368807 or get in touch online to book a repair or get friendly advice.