Member Since: 13 Feb 2010
Location: woodford green
Posts: 16
Loss of power
My disco3 is suddenly suffering with a loss of low down power below 2000 rpm can not see a split in turbo hose does anybody have any places to look for normal tell tale signs , no black smoke from the exhaust . Have ordered blanking kit for egr & going to clean MAP sensor have changed diesel filter does anybody have any ideas what may be causing this , is there a quick way to temporarily blank EGR’S to see if l can restore power to confirm or isolate the EGR valves . Anybody had problems with the variable blade turbo ?trevor weldon
6th May 2021 12:15 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4666
Diagnostics should be your first port of call, but check and clean the MAP sensor anyway. (do not prod or push anything into it) use brake or carb cleaner!
EGR's can cause similar problems too but you can do a temp blank using a coin (Stg 2p I think) and see if it makes any difference.
There is plenty of rubber pipework that can spring a leak, so check all of them thoroughly. The other common failure is the turbo vane actuator rod which can become stiff or siezed. Its an easy fix but you need to pull out the heat shields in the nsf wheel arch to access it. (Should be plenty written here if you do a search)
In more serious failures, a cracked inlet manifold can allow unmetered air into the engine, or in a worse case scenario a stuck open EGR can melt the manifold with the same effect. There are other possible causes such as fuel system,intercooler, or MAF sensor failure.
So with all the above, diagnostics really are your friend! If you can pull the codes there should be something logged hopefully pointing to one or more above! yµ (idµ - eAµ) ψ=mψ
6th May 2021 3:41 am
Spannerman
Member Since: 13 Feb 2010
Location: woodford green
Posts: 16
I do have fault code up for the egr , so will temporarily try to blank these off , l have a vague memory of Landrover assist blocking these off at the top end , buy undoing the spring clip, and inserting a coin/ disc at pipe junction ,anybody have diagram of this ? Can someone explain why the inoperable egr valve causes such a dramatic loss of power , my turbo does finally kick in a much higher revs / 3/4 throttle so is it fair to assume the shaft in not partially seized . Does anybody know how to eliminate the MAF as the problem l read somewhere to disconnect the plug and try to see if this makes it better any views on this ? I don’t have a code up for this so is it again fair to assume this is not a problem?trevor weldon
6th May 2021 9:01 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4666
An EGR fault doesn't always cause dramatic loss of power however in it often does depending on the type of failure. Both valves stuck open for example! If this were the case you would have exhaust from both banks permanently feeding into the inlet manifold causing an obvious reduction in power, but there are other failed EGR scenario's too with the similar effects particularly on EU4 protocol vehicles.(MY07>)
Fitting a temporary blank is as you describe, and is simple enough to do. More detail if needed is likely is covered on here if you do a search. A longer term solution would be to blank the EGR'S, remove the throttle butterfly, and fit a patch to the PCM so that it ignores them in the future.
I would not rule out the turbo actuator rod at this point, it may be moving partially but not enough to provide low end boost. This might explain boost at only higher revs. If you don't have a dtc for the MAF then it's safe to say the component is OK. Unplugging it will cause the PCM to select a "default" value for it to allow the engine to operate until it's rectified. That said, there should be a code for boost pressure/MAF correlation if the rod is not moving enough! What diagnostics are you using???
Start with the simple stuff, hoses, MAP, and EGR's, as well as decent diagnostics if you're not already using. yµ (idµ - eAµ) ψ=mψ
6th May 2021 2:16 pm
Spannerman
Member Since: 13 Feb 2010
Location: woodford green
Posts: 16
Thanks for your imput , l am awaiting EGR blanking kit , this is the only fault showing at the moment & will see how it performs when these are replaced :🙂trevor weldon
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum