EGR not working on TD5

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Ploughman

Member
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29
Location
8°43' E - 52°1' N
Hi folks,
I'm yet considering the rough running of my TD5 in a 2005 Defender.

On Monday after work discovered that the EGR is not working.

For this I tried the following: plugged handheld "Haw...ye" tester to diagnostic socket with warm engine at idle speed and testing EGR functon manually ("circuit tests").
Result of throttle test: throttle lever moving well when pressing the button
Result of inlet valve test: as this is hidden within the modulator housing and thus not visible without dismanteling everything I connected vacuum gauge to it's vacuum hose accordingly: pointer of gauge moves up to minus 0.3 bars approx.

So manual outputs seem to be OK.

Then led a polyurethane pneumatic hose throughout the hole for former AC lines in the bulkhead connecting vacuum gauge and solenoid vacuum valve for the EGR inlet: no pointer movement during a drive simulating several load conditions.

I think proper EGR function is mandantory for TD5 as EGR raises intake temperature level so that compression ratio can be relatively low (19:1 for TD5).

Tried this on two ECUs of NNN500020 / NNW501290 type with a standard mapping ("as delivered"). With none of both no EGR function performed although all sensors - for instance the brand new mass air flow meter - provide normal values.

I must confess that I've tried several mappings. Maybe erased something??

Any ideas?

Thank you!
 
Hi, so if you insist i'll help you figure it out but let's make some important things clear from the beginning:
1. the EGR is an EMISSION CONTROL system it was not conceived to help the engine or combustion but to reduce noxes,
2. proper function of it is mandatory as long as it's there cos a malfunctioning EGR will affect the engine running and can pollute more but even if it's working as it should the engine will run worst with it fitted than without it

i could fill up a whole page with it's throwbacks but i'm not in the mood, my recommendation is to get rid of it but if you want to fix it tell me what fault code you get for it cos if there's no fault code then the problem is more likely that the EGR valve is clogged with muck and doesnt let enough air in the intake also the MAP/IAT sensor must be very dirty because of it which can cause rough running as well...eventually how did you realise it's not working in the first place?
 
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EGR does not raise intake temperature. It basically chokes combustion as there is no Oxygen in the burnt gasses thus lowering exhaust gas temperature and inhibiting the formation of Oxides of Nitrogen.

It does do what it says on the tin but at the expense of performance, mpg, and engine intake cleanliness amongst other things.

If it is on the car then it must work but there is no requirement at the current time for a TD5 engine in the UK to have one fitted.

Most people simply remove the EGR completely ( I do this on all of my vehicles) or blank it off so the dirty exhaust gasses can not reach the intake when the EGR valve is open. On the TD5 blanking is not a problem but on other vehicles it can throw error codes (P0400 or P0401) and bring the CEL light on.

If you take the EGR valve off the manifold you will see the crap that it feeds back through your engine. Chances are you MAP sensor is blocked and the EGR valve is also clogged with oily soot which will affect how well your engine runs.

My advice is remove the EGR valve completely, clean out the intake manifold and the MAP sensor, and forget about it.
I think proper EGR function is mandantory for TD5 as EGR raises intake temperature level so that compression ratio can be relatively low (19:1 for TD5).
 
Hi all together,
thank you so much for all your prompt replies!

Yes, I do remember a fault code "EGR inlet stuck, closed" or so but it is already some time ago. Anyway, thereupon I dismounted the EGR modulator and of course I discovered lots of smeary soot sedimentations. Removed them with rags and break cleaner as good as possible.
Then fitted back everything and checked mechanical functions of inlet and throttle with the Hawkeye at idle and the pulse duty ratios during a drive.
So far, everything seems to be o.k....

I finally realised the EGR malfunction as I was confused from different readings of the Hawkeye and the new Nanocom Evolution I’ve recently purchased (believing it would be much better....).
Since last Monday namely the Hawkeye displays no action of EGR pulse duty ratios anymore but the Nanocom Evolution strangely enough does. Even more strange is that one of the EGR readings is displayed in the “wastegate” field.

Anyway, that’s why I did the test with the vacuum gauge on the passenger seat.

Yesterday I repeated all the mentioned again added by a self-made LED tester switched to the inlet solenoid lines: no light came up during varied load conditions.
 
Why are you bothering doing all this? Its a waste of time. Spend £30 and buy a blanking kit. Your engine will thank you.
Or simply cut a baked bean tin up and make a blanking plate to fit between the EGR valve and the exhaust feed pipe if you dont want to spend any money. If you fit a tin blanking plate to the exhaust manifold it will burn through in a year or so. Personally I'd remove the whole gubbins and be done with it.
 
the best is to remove the whole thing cos that simple blanking method without using a straight through pipe is good only for the Eu2 EGR version but if i understood well it's the Eu3 type in which case simply blanking the EGR inlet is not enough cos the system is working on the ILT valve too which will restrict the clean air flow on management request as the two valves are working together, when the EGR valve opens the ILT closes and vice versa(unless the modulator is unplugged and vacuum ports clogged)

in a nutshell ... get a bypoass kit and do the whole job...you'll not regret it
 
Yes it is the water-cooled EU3 type of EGR.

All the mentioned is worth a try - reqiured parts are ordered and those hopefully superflous are already back on the bench;-)

I'll give a report!

Thanks!
 
I may be doing this for my bro in law, he has the kit. But he is liable to shear the bolts, but I'm sure they are of a certain metal that will undo. I always spray them warm leave and then respray. I like the plus gas to soak in and help release them.
 
the best is to remove the whole thing cos that simple blanking method without using a straight through pipe is good only for the Eu2 EGR version but if i understood well it's the Eu3 type in which case simply blanking the EGR inlet is not enough cos the system is working on the ILT valve too which will restrict the clean air flow on management request as the two valves are working together, when the EGR valve opens the ILT closes and vice versa(unless the modulator is unplugged and vacuum ports clogged)

in a nutshell ... get a bypoass kit and do the whole job...you'll not regret it
Good point I forgot about the later EU3 spec engines. Also removing the complete EGR valve assembly removes all restriction from the inlet tract.
 
Hi!
Fitted the parts and took a ride carefully to operating temperature – as expected same behaviour as before: relatively smooth after start-up but again very rough and due abruptly drop of engine speed hard to shift.


Checked for fault codes: nothing detected neither with Hawkeye nor Nanocom Evo.

Obviously there's fundamentally something wrong - somehow the much-lauded pilot injection making a TD5 run “remarkable quiet” seems to be suppressed.
 
So, imo you should have started with describing the issue instead of concentrating on the EGR though,
1. Did you unplug the connector of the EGR modulator? if not do it and make sure it can't touch earth
2. Did you check for oil in the ECM red plug and injector plug in front of the head? ...if you find oil there replace the injector loom asap cos that might be the reason
 
Hi!
Fitted the parts and took a ride carefully to operating temperature – as expected same behaviour as before: relatively smooth after start-up but again very rough and due abruptly drop of engine speed hard to shift.


Checked for fault codes: nothing detected neither with Hawkeye nor Nanocom Evo.

Obviously there's fundamentally something wrong - somehow the much-lauded pilot injection making a TD5 run “remarkable quiet” seems to be suppressed.


Were the parts EGR removal kit?

If not why not?
 
Hi!
Yes fitted EGR removal kit consisting of the flanged hose piece and the blanking plate as recommended. Tried with both plugs off and secured not to risk shorts or touching vehicle earth.

To be honest I feel no difference.

But what's the use of all that? Main inspection is due within July and faulty EGR will probably result in a TÜV complaint anyhow. Maybe they don't take notice of increased noxes, maybe they do. If so I have to fit new ECU in car whilst a major thing persists.

I do associate rough running too with misfires caused from whatever.
Recently read about this:
"The engine may misfire and cut out at high revs/min or misfire then recover until throttle pedal is depressed again. This is most likely to occure when engine is warm or hot. MIL may come up"

Mine didn't show MIL illuminated so far but I remember a fault code logged "High-speed sync lost fault". After clearing this fault never occured again.

Anyone busy with mentioned?

PS: never had tracks of oil in red plug or bulkhead connector; AMR6103 replaced several times
 
You should have felt an improvement on a well running engine but as long as your's doesnt work well for some other reason the EGR bypass might not be noticeable... you was concentrated from the beginning on this EGR thing while there's some other problem with your engine management

that fault code which you erased is caused by the crank sensor but if it's not current it might not be relevant

unplug the MAF and drive it so to see if there's some difference or not...

did you clean the MAP/IAT sensor after the EGR removal? if not do that too cos it's full of gunk which can cause rough running

btw mine got lower emmision readings after the EGR removal cos the combustion was better, i've never heard about mot failure caused by bypassed EGR

as i said before, you should have focused on describing the symptom and curing it than insisting only on this EGR thing... but no worries at least it's ruled out now :)
 
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