disco td5 overboost

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i will defo be looking at the second option tomoz thanks

You can take off BOTH turbo end casings without a worry.

Just take care not to bash the turbine blades about.
The ONLY moving part is the shaft with the two rotor blades on it, and if handled reasonably it will be fine.

Taking out the bolts that secure the turbo body to the exhaust turbine casing might not be so easy.

HOWEVER .... you can test for this problem without stripping it at all.

Have a look at the waste gate lever while the engine is stopped.
The lever is in GATE CLOSED position.

Take off the operating rod, then move the lever fully the other way (waste gate wide open) and secure it like that with a bit of wire.

Go for a drive.

If there is no boost that is because the gate is open and it works.
The fault is probably not in the turbo.

If there is full boost even with the LEVER in "gate open" position, this means the gate disc or flap MUST be jammed CLOSED, preventing by-pass flow and causing over-boosting.

So easy to do so it would be my first check.

CharlesY
 
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hello update turbo is not the cause so still scratching me head so done the nanocom today again for faults on engine ecu faults read turbo charger overboosting and airflow. clear but come back. so checked ace ecu wich through a hole load of faults here they are...
fault 07-02 fuel used output drive over temp intermiten
fault 07-03 radiator fan drive over temp intermiten
fault 07-06 wastgate mod short circuit intermiten
fault 07-07 egr inlet throttle short circuit but no longer have egr removed the lot...
fault 08-02 fuel temp circuit current
fault08-03 coolant temp circuit current
fault 08-05 referance voltage current
fault 08-06 ambient air temp circuit current
fault 08-07 driver demand supply problem current so what does every one think about these..... info would be kind thanks does any one think it could be the engine harness as it was oil contaminated but no issues with oil any more and none presant to this day....
 
ecu checked no oil ingress also got spare one with same results no oil presant in the loom but there was before but sorted out about 12mnths ago and always check it every 2 mnths or so also checked earths added new earths to still same ??? but havent ckecked for chaffed wiring .. have checked by the air con pump but all is good.... its propper doing me head in now...
 
any more info would be great on these faults thanks

As most of the faults seem to be for engine sensors it might be worth checking the wiring loom around the bulkhead area in case it's chaffing through there. Out of curiosity does the loss of power only happen when the engine temp is warm/hot or does it do it when cold too?
 
it does it from cold to will have to check the wiring to see if it is the problem thanks its never got hot never over heated and does not use any coolant .. its serviced regulary and well looked after .... its just this one problem that is doing me head in ,...
 
it does it from cold to will have to check the wiring to see if it is the problem thanks its never got hot never over heated and does not use any coolant .. its serviced regulary and well looked after .... its just this one problem that is doing me head in ,...

The reason I was asking is because this thread all started becuase your turbo was overboosting but you haven't listed an overboost fault in the list that appeared after you cleared the original faults. It made me wonder if the coolant temp circuit fault was the real problem you are experiencing.

I've had a couple of coolant temp sensors go down on my 110. The sensors were still showing the temp was ok but they were causing severe and sudden loss of power very similar to that experienced with turbo overboost.
 
I have an idea .....


Find the nipple on the turbo outlet pipe, the nipple to which the wee pressure pipe connects. It is easy to feel, but not easy to see right away.

This wee pipe and the nipple MUST be clear, and no splits in the wee pipe all the way to the modulator box. Take the pipe OFF, and check it. Then make SURE the nipple is not blocked. If the pipe is split (or OFF) or the nipple blocked, your symptoms are spot on, and the fix is obvious.

If not, here's my plan:

Connect the turbo outlet pipe nipple direct to the waste-gate capsule nipple.

Cut the wee pipe and insert a tee-piece.

Connect the side of the tee-piece with a wee pipe to the boost modulator box input nipple.

Connect a short piece of pipe to the boost modulator box output (that used to go to the capsule) then block that pipe.

This might provide a fix meantime, but you may have to adjust the wastegate rod to get the pressure about 1 BAR max.

I can't see a flaw in this yet.
 
hello hi yes i did list turbo over boost and airflow but them faults were on the engine ecu these new faults are off the ace ecu when you read faults with nanocom i clear all faults but after a drive all return . ive set it up like defender now so i bypass the turbo boost acctuator control valve. but still same problem overboosting...
 
hello hi yes i did list turbo over boost and airflow but them faults were on the engine ecu these new faults are off the ace ecu when you read faults with nanocom i clear all faults but after a drive all return . ive set it up like defender now so i bypass the turbo boost acctuator control valve. but still same problem overboosting...


What new faults?

ACE ????? Is this cornering problems now?
 
hello hi yes i did list turbo over boost and airflow but them faults were on the engine ecu these new faults are off the ace ecu when you read faults with nanocom i clear all faults but after a drive all return . ive set it up like defender now so i bypass the turbo boost acctuator control valve. but still same problem overboosting...

Sorry. I forgot they were from the ACE ecu. I haven't had too many dealings with ACE ecu's (it's mainly discovery engine faults or td5 defenders that i get) so this is only a guess but.... On the engine ecu's there are several faults that come up purely because various bits aren't fitted. (tacho open load fault, air con open load fault, wastegate modulator etc). Is it possible that the faults that have come up are because the ACE ecu isn't linked to the items on your list so therefore they will show as standard faults on most if not all ace ecu's?
 
no ace problems no. ace ecu also stores faults from engine to why i dont know but a lot of the garages say to look there for faults because they store there to so i did and found faults and cleared them and they come back ....
 
One thing you have not mentioned is the result of live data displays - hook up yer Nanocom and go for a drive,max boost is about 225-230Kpa before the ecu will cut fuelling.
Is this happening ?
 
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