Hello there!

I am new here, so hi there and thank you for your help in advance! Here comes my case:

A few months ago my Display told me "DPF full". Furthermore the engine was not running as smoothly as I like it, so I first had the injectors tested. Some were already showing incorrect injection amounts, so, considering the 270.000 km I have already done, I thought it would be time for a general overhaul of the injection system and the exaust system. I still want to drive the car and not go to the workshop all the time!

So I did the following:

- Changed both EGR valves for new ones and teached them in.
- All tubes and gaskets around there new
- New glow plugs
- injectors completely overhauled and teached in
- Particulate filters professionally cleaned and teached in
- particulate differential pressure sensors new
- intake manifold cleaned

After finishing, all error were cleared. After the first test drive, the error P0407 "Exhaust Gas Recirculation Sensor B Circuit Low" popped up. I tried to delete it, but it won't do it. It's not that I can delete it and it pops up again. I simply cannot delete it!

Now I thought, maybe the new EGR-valve was faulty. Got a new one on warranty. Put it in. Result: Same error still!

Then I went to the LR dealership. He thought that maybe a complete system update would clear the issue. Done, but didn't work. No change. All cables have then been checked. New LR-dealer-idea: It may the the throttle body! Exchanged. However, no change!

Now their next guess is ECU problem.

Now I really don't know what to do, because it seems that LR is also only guessing and I think it's a little exagerated to change the ECU based on an a wild guess.

Did anyone have a similar experience or an idea about how to go about the diagnosis?

Thank you very much for sharing! I will definitely let you know how this goes on!

Stephan

On a freelander 2 TD4 ... the EGR Sensor B circuit error actually refers to the throttle body position sensor of the air intake system. It is possible this is the same on the TDV8.

Modern EGR circuits involve monitoring both the position of the EGR valve and the throttle body position to work out how much exhaust gas is being re-directed back into the engine.

You have stated that you cleaned your intake manifold. Have you checked that the throttle body is clean and working properly too? ( Is the cable attached ? ) V8 or else ...

If you are still stuck, you need to find the full error code.

Basic scanners report 5 digit error codes - ie A1234

Land Rover use a 9 digit error code - i.e A1234-56-78 You will need a dedicated land rover capable scanner to get this full code.

A1234 refers to the generic error code ( such as EGR Sensor B circuit ) - which basic scanners will report
56 refers to a sub section of that error ( such as throttle body, open circuit, closed circuit etc )
78 refers to whether the error is temporary/permanent/critical/non critical


To find out what 56 refers to, you might need to get a short access to TOPIX ( Land rovers online documentation ). Within the technical information, there is details about what each error code means including the 56 parts. V8 or else ...

Have exactly the same code on mine and i can clear it but comes straight back again. Asked on here before about it but didnt get any responses so asume its not a common one. I have no issues or errors and can see the egrs opening and closing on my iid tool so just put it down to a small gremlin as theres always a code showing for something. Found some info on the disco 3 forum and that was down to a cable unplugged in the inlet manifold.

What symptoms are you experiencing now everyhing else has been done?? Current 2007 TDV8 Vogue Buckingham Blue

Unnecessary quote removed

Fisha, thank you for the great ideas! The throttle bodies have been checked, too, but I will re-check the wiring there. If that doesn't help, I will go to the dealer again. I will let you know how it turns out!

kbald wrote:

Have exactly the same code on mine and i can clear it but comes straight back again. Asked on here before about it but didnt get any responses so asume its not a common one. I have no issues or errors and can see the egrs opening and closing on my iid tool so just put it down to a small gremlin as theres always a code showing for something. Found some info on the disco 3 forum and that was down to a cable unplugged in the inlet manifold.

What symptoms are you experiencing now everyhing else has been done??

hi did you ever resolve the issue - I have just replaced the egr valves and have the same error code showing?

regards

tom

Hello Tom,

in the end - after almost half a year - the issue was finally resolved:

The EGR-valves that my mechanic had ordered obviously do not go along well with the ECU. They were of Pierburg make - normally not bad quality. He found out because he spoke to a Land Rover mechanic who told him that often third party supplier EGR's have this problem.

After ordering two original LR EGR-valves, everything was ok.

Conclusion: In case you ever change your EGR-valves in your Land Rover: buy originals!

This was a very costly lesson for me (and the workshop).

Cheers!

Stephan

thanks for the response Stephan - much appreciated. The new ones that I fitted were valeo EGR valves (who supposedly make the oem ones) but not from JLR. I will refit the old ones this weekend and hopefully the faults will go away.

Thanks again!

tom

Tom, good luck! I am very interested in hearing about the result!

Take care!

Stephan

I would also have a look at the throttle position sensors as the workshop manual advises to check these with that code. Easier to check first before stripping out to put he old egrs in! Current 2007 TDV8 Vogue Buckingham Blue