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Boost actuator fault

hale-pope

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10 i-dtec tourer ex
My EML fault code suggests the boost actuator needs cleaning or replacing. It’s a 227k car so if it can be cleaned it’s ok but I ***ume it’s an expensive operation to change the turbo relative to the car’s value so I’m just trying to gauge if it is worthwhile.
 
The actuator pulls the vanes into position and is an external vacuum operated part. You do not need to pull the turbo to change it but it might be a touch finicky at the turbo end of the shaft. First inspect the vacuum line connected to it. If there is a leak the actuator won't work properly.

Surely someone here has seen the fault code.. I suspect a sticky turbo vane might be interpreted as actuator failure as well.
 
It’s electronic on these. If the error code was P00AF then most likely sticking vanes from previous build up or even a bit of rust on the actuator rod restricting its movement. More info and pics here:

 
Thanks both and for sharing the link. My car has was with you a few years ago @F6HAD and I when you got rid of the soot keeper (!) you either changed the turbo or cleaned it - I can’t remember which. That was probably 140k miles ago. Is it expected the turbo to soot up again? Hopefully it will respond to some delicate cleaning and freeing up and be good to go...unless that’s wishful thinking?!
 
We will have freed up and lubricated the actuator as part of the work, it’s worth doing that again. Make sure the engine is not running and manually move the rod up and down and run some engine oil down the actuator rod and keep moving it until it feels nice and free with full range of movement. If the problem persists then maybe it’s time to strip down and clean or replace it.
 
I have had the same issue come up the other day, it will occasionally put the car in limp mode only if I'm using cruise control? It wont let me delete the fault code either.
Still seems to be boosting fine, if anything it seems to be boosting a bit more than normal? I ***ume the acuator can't fully close or something.
I am interested in trying the turbo cleaner before stripping the turbo, mines on 164k, its had the DPF and egr deleted (egr has been switched off with a plate, hasn't been fully removed) for some years now as well as a 190bhp, 420Nm remap.
With lockdown i haven't been on many long drives for the last few months, only to and from work (6 miles each way) which is probably why this has happened.

I am willing to give it a go, looking at reviews it seems to work on a range of cars including simular turbo setups. If it can give me a few extra months it'll give me time to find a type s turbo ;)

Cheers
Rob
 
I have had the same issue come up the other day, it will occasionally put the car in limp mode only if I'm using cruise control? It wont let me delete the fault code either.
Still seems to be boosting fine, if anything it seems to be boosting a bit more than normal? I ***ume the acuator can't fully close or something.
I am interested in trying the turbo cleaner before stripping the turbo, mines on 164k, its had the DPF and egr deleted (egr has been switched off with a plate, hasn't been fully removed) for some years now as well as a 190bhp, 420Nm remap.
With lockdown i haven't been on many long drives for the last few months, only to and from work (6 miles each way) which is probably why this has happened.

I am willing to give it a go, looking at reviews it seems to work on a range of cars including simular turbo setups. If it can give me a few extra months it'll give me time to find a type s turbo ;)

Cheers
Rob


What code(s) are you getting ?
If t/they cannot be reset then it is a continuous failure that the ECU senses immediately (or almost) after start up.

Whilst I don't own an 8th gen, I was getting something very similar two years ago, I'm wondering if it is a worn throttle position sensor.
 
It comes up with:
P00AF
Turbocharger / supercharger boost control A module performance.

It comes on as soon as the car is started so must be permanent.
Actuator A performance, does that mean there's a signal failure? Or simply that it's stuck?

I've just given it a blast to hopefully get some heat in the turbo and burn off some of the buildup, seemed a bit more responsive but engine light is still there.

Cheers, Rob
 
Perhaps it is more complicated / expensive than I thought.


Sorry :(
 
If it’s happening as soon as you restart the engine then it’s sticking pretty badly I would say. Worth manually trying to free it up, you’ll be able to tell just from the feel of how freely it moves (or not if it’s jammed)
 
If it’s happening as soon as you restart the engine then it’s sticking pretty badly I would say. Worth manually trying to free it up, you’ll be able to tell just from the feel of how freely it moves (or not if it’s jammed)

Thank you i will have a look today, i briefly looked yesterday, to get a half decent access i only need to remove the manifold heatsheald? is there anything i can spray on it or is the blockage likely to be internal? Hopefully if it is jammed it isnt causing any damage, as long as i drive sensibly.

https://www.halfords.com/motoring/e...itives/wynns-diesel-turbo-cleaner-309104.html

I'm going to pick one of these up later, i got a halfords voucher for christmas so why not! If this can help until i have time to remove and clean it properly then I'll be happy.
 
the issue is internal but manually moving it can help dislodge any large debris and build of soot that is scraping when the vanes move. You have to be careful though, too much force can damage the vanes and the actuator so if some fairly moderate persuasion doesn’t move it, time to replace or refurbish the unit.
 
The classic method of clearing carbon and hard deposits is a concentrated solution of sodium hydroxide (caustic soda), though it is always emphasised not to use where aluminium alloys are present.

As an aside is the 8th gen turbo/exhaust system more susceptible to gumming up ? I hadn't seen similar posts within the 7thh gen section.
 
I would think with the close coupled nature of the DPF/Cat that a blocked DPF will tend to blow soot and cr@p back into the turbo.
7th Gen has all that stuff way down under the car.
 
Yep it’s all down to the dpf on the 8th gen unfortunately. You’ve got the combination of soot blowing back into the turbo and accumulating on the vanes and then the extreme heat from the dpf which scorches and hardens some of that soot eventually clogging up the turbo. This is why I always advise against forced regens on these cars, whilst it might give you some temporary respite it nearly always causes blocked turbos.
 
Hi everyone,

I have been having a look at the actuator and where it is getting stuck.
I can get it to move freely for most of its travel, it gets to about 5-10mm from the 'stop screw' before you can feel it hit a notch. You can overcome this with a bit of extra force at which point it then feels fine. I did this a few times and it seemed to free it up a little, not sure if that means the vanes are getting partially jammed on something?
Also, when the actuator in its 'normal' position with the engine off, is that closed? and when it hits the screw stop it's fully opened to dischargee the pressure?

Hope that makes sense, I quickly had a look on my lunch break so don't have long to write this up!

Cheers
Rob
 
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