30 August 2022
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A failed EGR valve will reduce your Defender's performance
: credit: © Dave Barker
The EGR valve is important for reducing air pollution. Dave Barker explains the symptoms of a failing valve, and how to replace it
Need to know
Time: 2 hours.
Difficulty: 2 out of 5 stars
Models: Defender TDCi.
Tools needed: General workshop tool, including 8 mm and 10 mm deep reach sockets, long extension and a wobble extension. Diagnostic test equipment to clear the fault from the vehicles ECM.
Parts used: 2.4 TDCi (2007 – 2011) LR006650, Exhaust Gas Recirculation (EGR) Valve including gaskets. Prices range from around £195 for a Genuine Land Rover part to around £83 for an aftermarket part.
Work safely:
• Wear protective gloves or barrier cream to protect the skin from oils and sharp edges of components.
• Disconnect the battery before working.
Contact: Maddison 4x4, Water House Farm, Station Road, Topcliffe near Thirsk, YO7 3SG. Tel: 01845 587407, maddison4x4.com.
Early environmental regulations led to engine management systems aimed at controlling exhaust emissions. The last of the 300Tdi engines had an exhaust gas recirculation (EGR) valve that returned small amounts of exhaust gas back into the combustion chamber, so reducing nitrous oxides in the exhaust gas from the tailpipe.
This was a simple valve which often failed because of exhaust carbon building up inside, causing the valve to stick in the open or closed position. Most owners simply unplugged it without affecting the car’s driving performance. The next generation of engine, the Td5, had a more complex EGR system incorporating an exhaust gas cooler and an engine management system that would warn you if the EGR failed – and affected the performance of the engine.
The later Ford TDCi engine fitted into Defender from 2007 took emission controls and engine management further. A failed EGR valve could almost stop the Defender, reducing the vehicle’s performance to an almost undrivable level. It also needed a diagnostic tool to first confirm the fault, and then to clear the fault and restore the engine’s performance.
The 2007 2.4-litre TDCi Defender featured here is used every day and is regularly serviced. It has covered 165,500 miles, almost trouble-free. But, recently, it suffered a sudden loss of power and the engine management warning light illuminated on the dash. Diagnostic test equipment showed a failed exhaust gas recirculation valve.
Luckily, on the 2.4 TDCi engine, replacing the EGR valve isn’t an overly difficult job: just four bolts secure it to the exhaust system. However, it’s a fiddly job because the valve is located down on the left-hand side at the rear of the engine and difficult to reach. It’s a touchy feely job, as you cannot clearly see the securing bolts – be prepared to drop the securing bolts and the socket several times.
There are two top bolts securing the valve to the EGR pipe, and two on the side securing it to the EGR cooler. Both sides of the EGR valve have a pipe-to-valve metal gasket which should be changed with the valve, and these are normally supplied as part of LR006650 with the EGR valve. The stored EGR fault code will need to be deleted from the Defender’s ECM using a diagnostic tool to restore the EGR system settings, bringing the engine back to full power.
Warning sign: The Defender TDCi suffered a sudden loss of power, this was accompanied by the orange (engine related problem) warning symbol on the instrument panel.
Option to remove: Yellow arrow points towards the EGR valve. Manual suggests removing heater control valve (white arrow), but bolts accessible with an extension and wobble bar.
Disconnect: It’s important to disconnect the vehicle’s battery first before starting any work, then the multi-plug wiring connection is disconnected from the EGR valve.
New valve to demonstrate: This new valve shows the bolt positions: two 8 mm top bolts secure the valve to the EGR pipe and two 10 mm side bolts secure it to the EGR cooler.
Locating the bolts: The securing bolts are difficult to see, but can be identified by feel and released with a socket with a long extension bar and a wobble bar.
Threading it through... By using the long extension bar and threading it carefully between the heater pipes, the socket reaches onto the top two EGR securing bolts.
Care needed: As the two upper bolts are released, great care is taken to avoid dropping the bolts down the side of the engine – difficult to retrieve.
Another tricky location: The two side bolts securing the EGR valve to the coolant pipe are undone using a ratchet and a 10 mm socket. Again, they are fiddly to undo.
Ready to withdraw: With all four bolts removed, the EGR valve can be wiggled out, while at the same time collecting the two metal flange gaskets (arrow).
Signs of damage: On closer inspection of the EGR valve, there was a large build up of carbon on the valve itself, inside the assembly, possibly causing it to be stuck.
New valve: The new replacement EGR valve, branded Lucas in this case, is complete ready to fit, and is supplied with the important two new metal gaskets.
How it should look: Here’s a view of the new EGR unit’s internal valve face. Before installing the valve, the mating faces of both pipes are cleaned of old gasket debris.
Bolts and gaskets: After feeding the new valve into position, the securing bolts are fitted through the flanges and the new gaskets, and screwed into the EGR and coolant pipes.
Note: The best approach during re-bolting was to fit one bolt through each flange and gasket, then align the gasket with the second hole and fit that bolt. After tightening equally and evenly, all four bolts are finally torquedto 23 Nm.
Clear the code: The muti-plug and then the battery are reconnected, and the diagnostic tool is connected to delete the stored fault code, thus restoring full performance.
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