Xsara II 2.0 HDI 90 Fuelling Issues

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dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

I connected, scanned and read the faults, then clear them. Rescan for faults and only the evaporator and the IAT remain.
All good.
Next day I've came back, connected and scanned and they are all back again.
The faults are those on page 1 from last Sunday.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

Any ideas as to where to go from here? The diagnostics shows that the both sensor supply voltages (1=camshaft, 2=others) is 4.99V which is correct. I guess I need to ensure that this 5V supply is getting to the sensor and then do a continuity check on the wiring back to the harness input to the ECU.
How do I ensure that both the IAT and the MAF are correctly operating?
The resources online state don't buy a new sensor unless it is proven to be faulty.

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GiveMeABreak
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Re: Lexia install problem

Post by GiveMeABreak »

I'll have another look - I'm just catching up with posts as I was off line for most of yesterday sorting out networking issues at home.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

GiveMeABreak wrote:
07 Oct 2019, 12:43
I'll have another look - I'm just catching up with posts as I was off line for most of yesterday sorting out networking issues at home.
No rush - I wasn't posting for anyone in particular to respond to. Partially documenting my thoughts for when I get some more time to go and investigate it.

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GiveMeABreak
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Re: Lexia install problem

Post by GiveMeABreak »

Unfortunately early diesel codes for your Bosch system on a DW10D engine are not readily available, so I would delve into the fault code on your Lexia - by seeing what info (if any) it has.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

Okay thanks.

I've been in contact with some folk and the advice is as follows:

1. Injector 4 is kaput. Correction values should be less than 1.5.
2. Connect up the Lexia and drive about whilst monitoring the IAT value and check that it varies in accordance with the outside temp.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

I don't have my Lexia laptop with me during the week, so hopefully someone can answer this question:
How much data can the Lexia logging file hold (I assume it logs all ECU data over the timeframe) and can it be viewed/presented outside of Lexia? If not can it be presented graphically in Lexia? Does the 5 green traffic lights indicate it can store up to five sets of logging data?
Apologies, I know this information should be in the manual and I'll be able to check at the weekend, but I thought I'd ask now so I can hit the ground running on Sunday.

Does the 'Main Brake Signal' in the drivers information screen refer to switch coming off the brake pedal?


Thanks.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

Can someone provide me with a diagram showing the location of injector 4?
I presume it is 1 to 4 left to right as you look into the engine bay - i.e. injector 4 is closest to passenger side.
Or does it go 1 to 4 from the gearbox side? I've seen both.

Edit: I've checked the Mechanics Handbook for the Xsara that is in the Citroen subforum and if I've understood it correctly, the DW10D engine has the RHY code. Pages 76 & 77 show the cylinder head, but do not display the cylinder numbers.
The TU/TUD engine on pg 67 shows cylinder numbers but does not note if the numbering relates to all.

I believe I can disconnect the injector and check from the Lexia, but is there another way?

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

What does the main brake signal refer to in the driving information screen?
When I press the brake, the indication does not change from released. The exterior brake lights work fine.
Should pressing the brake switch change the 'Main Brake Signal' indication?
The info screen states that it is the 'information given by the vehicle brake pedal sensor'.
The redundant brake signal is used for the cruise control.
The clutch indication works fine.

Injected flow ref is 9mm3/stroke. Ref States 5 - 7 mm3/stroke.
Accelerator pedal hard spot signal 2 is pressed. Ref States or should be released.
Difference between measured and ref fuel pressure -6 bar. Should be 0.
Injected fuel flow reference is 12mm3/stroke. Should be between 5 and 7.
After warming , injectors 1 and 2 are .0.59mm3/stroke and -0.43 respectively. 3 is 1.9 and 4 is 2.3.
Measured air flow is 441.1mg/cp. Should be between 200 - 290mg/cp.
Fuel pressure regulator current is 520mA. Should be between 600-630mA.
Pre injection advance is +13deg. Should be between -11 and -9.
Main injection advance is 1deg. Should be between 3 and 4.
3rd piston deactivation is yes. Should be no.
Injected flow ref is 10mm3/stroke. Should be between 5 and 7.
Exhaust gas recycling valve electrovalve open cycle ratio is 5% . should be between 70 - 95.
Exhaust gas recycling throttle electrovalve open cycle ratio is 5%. Should be between 64 and 70.


Sorry for the formatting, on phone in garage at the minute.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

See images attached:

Note the fuel pressure difference between actual and ref flickered to -2bar as I took the image. Should have been -6 bar as per the text.
Attachments
IMG_20191012_212205.jpg
IMG_20191012_212511.jpg

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

About 15 minutes previously to the above values, I got these values. Note the injector correction values. I've no real idea what is going on.

I suspect that the MAF is goosed and until I get that fixed everything else can be corrupted, correct?
Attachments
IMG_20191012_210744.jpg
IMG_20191012_210008.jpg

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

Where can I get a pin out diagram for the ECU so I can check the wiring from the brake switch to the unit?

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GiveMeABreak
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Re: Lexia install problem

Post by GiveMeABreak »

I've had a look at what I have and there are no diagrams showing for 99% of the Xsara systems, so unfortunately I can't help you on this one.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

No problem. Thanks for checking anyway.
I might get back to you at a later date about why faults relating to an old ECU are still being flagged by the Lexia and not clearing out of the system.

The MAF (Siemens 5KWS623 - 9628336380) is definitely problematic. I've put the multimeer across it and got the following

PIN Signal
1. 5V when disconnected. 2.9V when connected.
2 12V Supply
3. Gnd
4. Blank
5. 2.6V @ idle increasing/decreasing linearly with engine revs
6. Gnd


This layout doesn't make sense. Something is definitely wrong. I'm trying to source a pin layout, but it is odd that when the MAF is connected it pulls the 5V rail down to under 3V - engine idle or off.
Also two supply voltages and 2 gnds for one signal is odd at first glance.
Looks like a new one is required.

dave_xsara
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Re: Lexia install problem

Post by dave_xsara »

Marc,

Do you know which MAF part number you post in this thread refers to?
viewtopic.php?t=62673