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Fine When Cold, Power Loss When Hot
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Cammmy   
Tue Jun 30 2020, 04:33pm
Joined: Mar 31 2020
Member No: #4291
Location: Essex
 Hi All, thought I would share this as it took a lot of searching to find the answer.

My 2.7 had an issue where it would drive okay when cold but then become totally lethargic after 10-15 minutes. A thread on here pointed me to the fuel filter, which I changed but it did not fix it. I got a code scanner on there and saw P0247, which is the wastegate actuator for the front turbo.

These actuators work differently from the ones of old. There are no springs or reference lines etc. It's totally electromechanical. Citroen (and other manufacturers) say that this can't be seperated from the turbo and it's not replaceable. The whole turbo has to be changed. I'm not one to believe that kind of thing, so while it was a total pain, I got the unit out and had a look inside. I tested the motor from a battery and it was okay, so I figured it must be the controller. I noticed that there are little wires soldered from the housing to the PCB and that one of them had broken. The contact is zinc coated, so I filed it back to copper, got it soldered on and then covered it in some epoxy.

Letting it hang, the unit will now home itself when the ignition is switched on, where it did not before. I haven't driven it yet as I have some other bits and bobs to do, but I'm fairly confident that will sort it.

Hopefully this saves someone from being ripped off.

It took the whole day to undo the three bolts, solder the wire and get it back in. The catalyst is totally and utterly in the way. I tried to remove it but it seems you really need the front of the car off to do that, so I persevered.
C6Dave   
Tue Jun 30 2020, 05:36pm

Joined: Oct 01 2009
Member No: #1
Location: Northumberland
Citroen (and other manufacturers) say that this can't be seperated from the turbo and it's not replaceable.

One of our very good dealer contacts gave us the answer to that some years ago: A lot of items on cars these days are deemed 'non repairable' simply because dealers carrying out 'repairs' would be liable for the guarantee should they fail and margins being what they are they simply say the whole part has to be replaced plus factoring in labour costs it's more 'economic' for them to replace rather than repair.

It's good to see that you managed to find the issue and a fix and have shared it for others to see as that is going to become more important as the cars age and replacement part supply dries up.
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321dave   
Wed Jul 01 2020, 12:46pm
Joined: Sep 09 2011
Member No: #614
Location: Dublin
 Hi Cammy,
was just wondering reading your excellent post, how did you get in to remove the turbo unit as you say it’s very tight in that part of the engine?

I myself would thought to remove the whole front section as you say. But its very good if you were able to somehow get to it.

321dave
Cammmy   
Tue Jul 07 2020, 01:26pm
Joined: Mar 31 2020
Member No: #4291
Location: Essex
 No problem, just to be clear, I only got the actuator out. Not the whole turbo.

Hard to describe but it was really just a combination of different lengths/shapes of spanners. You also need a socket and wobble joint to undo the heat shield bolt and shift that out of the way of the top actuator bolt.

To get the unit out, solder it and put it back took most of the day but I wasted time trying to get the heat shield off the cat. be prepared to lose some skin forcing your arm up through whatever gap you can.

Unfortunately it didn't fix my issue. I still have the code and limp mode issue. Not sure if my soldering immediately failed or if something else is broken. I need to get my hands on another unit to just plug in and cable tie somewhere to see if the code goes away.
321dave   
Tue Jul 07 2020, 09:45pm
Joined: Sep 09 2011
Member No: #614
Location: Dublin
Cammmy wrote ...

No problem, just to be clear, I only got the actuator out. Not the whole turbo.

Hard to describe but it was really just a combination of different lengths/shapes of spanners. You also need a socket and wobble joint to undo the heat shield bolt and shift that out of the way of the top actuator bolt.

To get the unit out, solder it and put it back took most of the day but I wasted time trying to get the heat shield off the cat. be prepared to lose some skin forcing your arm up through whatever gap you can.

Unfortunately it didn't fix my issue. I still have the code and limp mode issue. Not sure if my soldering immediately failed or if something else is broken. I need to get my hands on another unit to just plug in and cable tie somewhere to see if the code goes away.


Thanks for the update Cammmy. Sorry the initial work didn’t pay off yet. Good luck with the rest of the
repair.
Cammmy   
Wed Jul 08 2020, 09:12am
Joined: Mar 31 2020
Member No: #4291
Location: Essex
 Thanks, I'm trying to get hold of another actuator, just to test if it clears the code before I go to the effort of pulling it back out.
321dave   
Wed Jul 08 2020, 04:58pm
Joined: Sep 09 2011
Member No: #614
Location: Dublin
Cammmy wrote ...

Thanks, I'm trying to get hold of another actuator, just to test if it clears the code before I go to the effort of pulling it back out.


That’s a good idea. Hopefully you’ll be sorted. After doing a few hard jobs it sometimes seems to get easier.
Paulius   
Sun Jul 12 2020, 08:13am
Joined: Aug 14 2014
Member No: #1821
Location: Vilnius
 I had the same exact issue with my rear turbo over a year ago. I did take the actuator out, bring it to a turbo specialist who reported that the electronics were dead. They told me that it is not that uncommon for older cars, as the back turbo is exposed to higher temperatures which leads to failure over time.

I then bought a used actuator (separately from the turbo) from a donor vehicle, popped it in with no calibrations or whatnot and it works fine to this day.

However, a month ago the front turbo actuator started this exact behaviour when it would only work properly when cold. Already bought a donor actuator.

When buying used actuators, they sometomes mix rear and front ones up. There usually is a number on the metal part of the housing of the actuator, and the numbers are as follows (for the 2.7): G-227 for the rear, G-226 for the front.
Cammmy   
Tue Jul 14 2020, 09:19am
Joined: Mar 31 2020
Member No: #4291
Location: Essex
 Nice one, thanks for that.
Cammmy   
Thu Jul 23 2020, 10:14am
Joined: Mar 31 2020
Member No: #4291
Location: Essex
 Okay, so I got a pair of actuators from a Jag 2.7. they were slightly different (the arm was shorter on the Jag unit), so I took the top of the Jag unit with the PCB and mounted it to the body/motor of the original (making sure it was a front turbo actuator PCB). That cleared the error but now everything is so much worse.

The car idles fine but is barely able to move under it's own power and under any load it has a massive diesel knock and black diesel smoke comes from the back of the engine. Has fixing the front turbo brought the car out of limp mode and now exposed a dead rear turbo? Or has mixing and matching the actuator somehow immediately killed something? (I don't really see how). There was an error about airflow mismatch. I swapped out the MAFs just to see and the error isn't there but the symptoms haven't changed.

I will unplug the actuator and see if it goes back to driving how it did before (fine but just in limp mode).

I'm not interested in taking it to a mechanic unless it's something that is likely to be simple but I just don't know enough about diesel's to realise. I have a bunch of projects I'm working on and the car was given to me by my dad who bought it sight unseen.
Cammmy   
Fri Aug 07 2020, 06:38pm
Joined: Mar 31 2020
Member No: #4291
Location: Essex
 Okay, I've recovered the situation. It turns out you definitely can't cobble together an actuator. I got diagbox and saw that one bank was getting about 25% of the flow compared to the the other. My theory is that the controller was calibrated differently and was fully closing the VNT, essentially choking that bank. I bought a remanufactured unit from Turbo developments on ebay and it's sorted the issue. It was £130.
 

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