2.2 HDi poor cold performance

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Rp0thejester
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Re: 2.2 HDi poor cold performance

Post by Rp0thejester »

Just a few photos
IMG_20240303_120750.jpg
my unplugged MAF sensor, its staying that way! It seems to make no difference in mpg, it just puts you in limp mode when it fails, if it's not connected it can't fail. I haven't used Lexia to tell it that it's unplugged or deleted and works great. Next photo
IMG_20240303_120805.jpg
this is where my air pipes separated behind the MAF hidden at the back of the engine, silver tape to the rescue. While they were separated I did have issues of no acceleration uphill whilst stamping on the accelerator several times as if the car wasn't in gear but only happened in hot weather. Next photo
IMG_20240303_120721.jpg
I assuming these are the EVs your talking about, i find the left one will get warmer than the right but not by much. If one is alot hotter than the other then the filter might be blocked on it. Stick your finger on it and see if it sucks, if it doesn't that's an issue. If I think of anything else I'll let you know.
Ryan

'99 Xsara 1.6 X (Red) with Sunkissed bonnet. T59 SBX
'54 Astra Estate 1.7DTI (Artic White)
'06 C8 2.2Hdi Exclusive (Aster Grey)

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Yes I ask the stupid questions, because normally it is that simple.
PaulC5
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Re: 2.2 HDi poor cold performance

Post by PaulC5 »

If the MAF is disconnected and the engine management light is on then surely it will fail the next MOT.
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Rp0thejester
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Re: 2.2 HDi poor cold performance

Post by Rp0thejester »

PaulC5 wrote: 03 Mar 2024, 16:49 If the MAF is disconnected and the engine management light is on then surely it will fail the next MOT.
Nope, anything before and including '06 with an EML is a pass if everything else is up to standard. It's only after 06 that it's an instant failure. I've quizzed Marc lots on this
Ryan

'99 Xsara 1.6 X (Red) with Sunkissed bonnet. T59 SBX
'54 Astra Estate 1.7DTI (Artic White)
'06 C8 2.2Hdi Exclusive (Aster Grey)

Champion of Where's CitroJim :-({|=
Yes I ask the stupid questions, because normally it is that simple.
MixerFistit
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Re: 2.2 HDi poor cold performance

Post by MixerFistit »

Rp0thejester wrote: 03 Mar 2024, 16:15 I assuming these are the EVs your talking about, i find the left one will get warmer than the right but not by much. If one is alot hotter than the other then the filter might be blocked on it. Stick your finger on it and see if it sucks, if it doesn't that's an issue.
Thanks for the pics.
The left one is EGR. It's hot as it's stuck on (even without filter). It was on the turbo (right) but was swapped as egr was getting disabled while I fault find.
The other 2 EVs are to the right of the airbox stacked vertically (the top one is visible in your second pic) and these were stuck on too so with both constantly pulling a vacuum my intercooler inlet was closed and heated inlet stuck open. They've been blanked at moment too.
The new MAF is coming in a few days, which although i could pull this one like you've done, as I have an ongoing issue I'm trying to get it back to stock config.

I'm still leaning to injectors and/or fuel pressure regulator. The FPR looked clean but the gauze is so fine I'm not sure a blockage would be visible.

My idle fuel pressure is about 259 to 267 bar which appears to be too low. But the 'Difference between measured and reference' seems to fluctuate between +10 and -14 bar even (though the measured pressure doesn't fluctuate as much) .
I've read a good idle pressure is around 310. So is that a misbehaving FPR or is it an injector going nuts?
I don't think there's much if any loss in power when giving it a blast up an inclined bypass in 4th/4k RPM so I'd assume the HP pump itself is good
2005 C8 2.2 HDI 4HW - 6 Seat, Exclusive

2006 Dispatch 2.0 HDi RHZ (SORN)
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Rp0thejester
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Re: 2.2 HDi poor cold performance

Post by Rp0thejester »

Once again I will say you are over thinking things. Get back to basics and ignore the computer data! An engine will run if it's right, old Bentley superchargers worked with no electric computer, cars used to be hand started no electrics involved, go back to basics. If the engine is running then it's probably an electrical issue. Removing parts will not help in finding the issue.
Ryan

'99 Xsara 1.6 X (Red) with Sunkissed bonnet. T59 SBX
'54 Astra Estate 1.7DTI (Artic White)
'06 C8 2.2Hdi Exclusive (Aster Grey)

Champion of Where's CitroJim :-({|=
Yes I ask the stupid questions, because normally it is that simple.