hdi 110 loss of power

[harryp]

As far as I can see, the pipes are all ok, no splits, no leaks. However, there is oil leaking out of the n/s side of the intercooler so it needs replacing. As previously noted, I have 25" vacuum as per my Mity Vac which I have had for over 40 years - gosh time flies. Will double check and check the waste gate. Bye for now

[citroenxm]

The intercooler leak could well be the whole cause then.. doesnt take a lot to loose power..

[harryp]

The loss was very sudden! Intercooler needed anyway. Will report back tomorrow on waste gate etc.... Regards

[Gibbo2286]

There is no oil in the intercooler it is an air to air cooler, if you have oil there it is coming from somewhere else. Here's a video of what an intercooler is and what it does.
https://www.youtube.com/watch?v=6nhLE1LI2BQ

[citroenxm]

Oil in the intercooler is because of either turbo seals weeping which id not worry about untill theres blue smoke pouring out the back or a breather is sucking it in somehow.. but yes its an air to air cooler.. the only psa to use a water to air cooler is the big 2.5 td engine as used in series 2 xm

[Gibbo2286]

Whilst you are under the car you should pull the vac pipe off the turbo actuator and check if there's vacuum there (at the pipe), if you have vac there and have access to a vacuum pump you can test if the actuator is working by connecting your vac pump directly to the actuator.

I'm not sure what make the turbo is on the Xantia, the C5 HDI has a KKK (Borg Warner) turbo and there are two different versions, one which is by default open and the other by default closed so you need to find out which before getting too deep into diagnosis.

It's unlikely that the actuator has failed, only very very rarely they have a diaphragm perforated which will mean they don't work and unless the setting has been tampered with there should be no need to adjust the link.

[citroenxm]

Im pretty certain that all hdi xantia turbos on the 110s are default open wastegate... but im not sure of the turbo make.

[harryp]

Have checked all again. Getting 25" vac. Wastegate free to move but does not. Tried 3 electro valves, still not working. Using Mity Vac on pipe to EV and wastegate moves and confirmed by Vac direct to wastegate and waste get now moves, and turbo pipe swells! No idea why it didn't before
Checked contacts to wiring and no dodgy contacts to wires.
Now I would guess that something tells the ECU to use the Vac to get the EV to move the wastegate. I am guessing that the sensor to do that is the one on the intercooler?? Only problem there is if it's saying the pressure is 998Mb, would expect full boost. There is a pipe? which comes off under the sensor but cannot see where it goes without removing battery and carrier and swmbo says them indoors are getting faint with hunger so have had to stop for the moment. Cannot remove the sensor at present as it is corroded solid, so will soak in easing oil and wait. The sensor does not appear to be connected to the intercooler, so where is it getting the pressure from, and why is it mounted on the intercooler??? Very, very confused I will see what Lexia says after tea.

[RichardW]

I suspect it comes off the metal elbow where the it goes to the inlet manifold - I've had the pipe off under the engine, and the one from the IC to that elbow and not seen the pipe.

Not detecting boost shouldn't stop the ECU asking for it in the first place I wouldn't have thought. Have a look at the live data on Lexia, and see what the turbo electrovalve position request is doing - it should rise (or fall perhaps!) as the load increases and boost is requested. What is the air flow saying? It should be about 400 at idle and rise steadily as the revs rise - and you should see a step change if you disconnect the vac to the EGR electrovalve when the engine is idling. Does the pressure change at all from 998mbar? Air pressure is relatively high today, so it should be reading more than 1000 mbar before the engine is started. If you apply the vac direct to the turbo and open the wastegate does this give improved performance (don't go mad!)?

[citroenxm]

If you shut the wastegate with a direct vacc and the ecu detects over boost this confirms the boost sensor ontop of the intercooler is working.. it will put the car in safe mode but a key off and reset will clear it and resume full power till next over boost is detected..

[harryp]

engine off

injectors all 0.04
airflow 182.4
EGR valves both 5%
Pressure 1035 setting 1247
airflow 182.4

engine on

injectors 0.82, 1.29, -1.61, -0.59
airflow 417.6
EGR valves 99 and 79%
Pressure 1035 setting 1153
airflow 417.6


Faults
Turbo press measured too low, 1082, setting 1600
Turbo press EV s/c or o/c
Flowmeter s/c or o/c
EGR o/c
EGR s/c to +ve

revving engine, press drops to 998 which confirms suck as per norm aspirated engine
(edit) when revving stationary above, engine misses quite badly - also noticed this climbing Haldon Hill - see previous.

It still appears to me as though the electronics are at fault somewhere

Will have to drop car to use on road with vac directly to Wastegate to check I actually get the boost apparent up in the air! More tomorrow.

[Stickyfinger]

??? injectors 0.82, 1.29, -1.61, -0.59 is that correct ??

[citroenxm]

Yes those injector corrections are not bad readings at all i think

[RichardW]

Odd that the MAF is reading a flow with engine off.... may be a red herring though. What happens if you clear the faults - do they all come back immediately? What did it say about the turbo pressure valve? I can't remember if this ECU uses a 5V control voltage - possible that if one of the components is faulty it is pulling down the reference volts and causing all of them to go haywire. I wonder if the earth from the ECU might have been disturbed - but I have no idea where that is!!

[harryp]

Thanks for replys.
Yes readings are injectors!
Yes, thought some of the readings bizarre too. Haven't done anything more yet - at hospital with father in law from 2am and just back, feeling a little the worse for no sleep! Will check the live readings with vac applied, and then go for a run in about an hour. BTW any info as to earth would be appreciated.
Regards and thanks