Release your TD5 power!!

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apologies for reviving an old thread BUT hopefully it may be of use to someone. My actuator rod diaphragm had a tine hole in the metal housing (possibly caused by contact with the heat shield).
I only identified it as i was doing some fettle action on the waste-gate actuator arm. I fitted a pump to the diaphragm and could see the rod move with a little pressure but the rod would then go static and pressure would escape from the tiny crack in the housing. From research it appears this is not uncommon.
I cleaned and buffed then used high grade e-metal stuff to execute a battle damage repair. Now when i tested with the pump the rod smoothly flows all the way out with no loss of pressure. Test drive shows increased response and turbo whistle.
Having just fitted a new pump this has been a satisfyingly cheap fix (look to sky with prayer hands!!!). PS don't use exhaust putty - it wont hold.....!
 
you better make sure it's well fixed cos you might loose vacuum there and have breaking issues as it's from the same vacuum circuit...and that could be dangerous
 
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Apologies i may have confused the issues when i wrote that i had fitted a new pump - i was referring to a new in-tank fuel pump (££). Just glad ill not be forking out for a turbo - I couldn't find the diaphragm as a component item anywhere.
 
Sorry for reviving an old thread but my 2003 TD5 auto Disco 2 suffers the occasional 'hiccup' or hesitation under load. Done all the usual stuff - injector harness etc. The wastegate actuator was stuck when I checked but with WD40 and using mole grips on the rod, it has freed up and has a fair amount of travel. But I'm surprised at the amount of effort required to operate the rod - there must be quite a spring it's working against. Is that right? Should I be able to see the rod moving if the engine is revved?
 
Sorry for reviving an old thread but my 2003 TD5 auto Disco 2 suffers the occasional 'hiccup' or hesitation under load. Done all the usual stuff - injector harness etc. The wastegate actuator was stuck when I checked but with WD40 and using mole grips on the rod, it has freed up and has a fair amount of travel. But I'm surprised at the amount of effort required to operate the rod - there must be quite a spring it's working against. Is that right? Should I be able to see the rod moving if the engine is revved?
Yes it should put up a fight when trying to move it by hand. The important thing is that it can move with full travel from closed to open.
 
This is interesting.
l posted a thread last year about adjusting the wastegate and was told that it's not that simple.
l tried adjusting mine (from 13 threads showing) got to 10 threads showing and there seemed to be no difference.
However it was running standard tune at the time, now it has a remap.
I also believe the wastegate works differently in Discovery than Defender?
So with the Defender remapped will adjusting it make any difference?
 
If l remember correctly l was told that shortening the wastegate rod (on a Defender TD5) won't increase the boost but will make the turbo come in more quickly and at lower RPM.
 
OK.

I'll give it a try then. Last time l got to 11 threads showing (from 13)...which was the most that was recommended on the other discussion...on a standard Defender and there was no noticeable difference
 
I'm not certain anybody really knows what happens when you wind the wastegate rod in.
l can't find any definitive answers. Some say it increases the boost. Others say it can't as the boost is controlled by a sensor, and it just makes the turbo reach full boost faster.
Then some say you can't just twiddle the rod as the engine will under fuel. And it can be done on a standard engine/can't be done on a standard engine
Plus the Discovery TD5 works in a different way.
 
I am writing to share my experience lately.

If you look back, i've had a few threads related to surging/stutter problems.Ive spend a lot of time on this trying to figure out my problems one by one.

I've learned three things:

1) Removing the mid-silencer will reduce the exhaust resistance and may cause your td5 to get a little surging feel. Not big time - but in combination with the two following issues it is amplifying the surging/stutter problem.

2) The CV joints. It's well known I believe? If the splines are worn you will get a surging feel when engaging gears etc.

3) Now this is the most important one. My td5 has a AliveTuning remap, bigger intercooler etc - in general a nice setup. After the remap - the stutter and surging feel was very predominant. The workshop statute it to be a general/different engine problem - amplified by the remap. Trying to solve it - we fitted an new ECU (ouch!), throttle pedal, I exchanged the complete! engine harness myself, the injector harness, the MAf etc. All the usual stuff - expensive though! It was never solved. #1 and #2 helped - but the problem was never solved for real.

The past months I have also wondered if my engine really was providing the bhp/Nm which it should - considering the remap etc. I had this feeling that it was not. But you know - as time goes by you forget the reference point (122 bhp) ...

MOT came up - and I failed big time on the exhaust gas.

Something must have been wrong so I started goggle'ing again. A good friend also led me on the right path. Waste Gate adjustment. The workshop I used for the remap missed out on one very important setup issue - adjusting the waste gate!

I have a Nanocom so I could monitor the inlet manifold pressure.
I decided to start reducing the length of the waste gate rod until the point I hit 'limp-mode' and then extend the rod a bit again.

I took along drive, adjusted the rod a bit, drove again and and adjusted - full turns ..

I was almost crying. By every turn i reduced the length of the rod - the more Grunt I've got. The potential of the td5 was revealed turn by turn. The inlet kpa pressure curve slowly moved down towards the lower rpm and the peak kpa did as well.

I settled at the point where my peak pressure was 230kpa and without going into limp-mode. The turbo pressure at the low rpm is also a lot better. I probably moved the pressure curve down to the lower rpm by 500-700rpm!

The engine runs like a train now!

More important though - the stutter/surging issue has disappeared! So - the problem was really - that the waste gate was open at the low rpm even when the turbo pressure was low. The surging was amplified by the waste gate opening/closing along with the small throttle movements during the jumpy/surging/stuttering physical movement of the vehicle. So by adjusted the waste gate I believe it now runs completely closed at the low rpm and only opens gradually when I reach one bar boost. Anyway - it helped. I might turn it a bit more as i would like to increase my low-end torque a bit more. But I am close to hitting limp-mode.

So - adjusting the waste gate gave me three direct improvements:
1) A lot better low end torque..
2) Much more power..
3) The surging issue disappeared!!

Honestly - I've been sick and tired of my LR and considered to get rid of it.. But now .. I happy again!! BIG TIME!!

Best regards
Lars

(Sorry for my english language/phrasing - I hope you got the point ...)

Very informative thread Lars. I'm delighted to know that you're happy again
 
About the wastegate thing...it depends very much about hiow the whole management works, on a perfectly working management shortening the rod with care will deffinitely improve throttle response at lower revs and increase final boost up to the overboost limit as long as the boost was not there already thanked to a remap. Though with shortened rod the wastegate will have shorter travel, the valve's spring tighter so the boost will increasee faster and drop more sudden so not a linear behaviour, that will make the vehicle to be jerky on fast throttle release and kick down...

as about D2s and Defenders, the difference will be greater when it comes to modulatorless Defenders which AFAIK were made for export cos the most of the UK modells have wastegate modulator so not much difference... if you want to play with boost the best is to not shorten the rod as the spring to be very tight and better control the boost with something like this http://www.ebay.com/itm/320679007155?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT
 
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