wurlycorners '96 Xantia Activa - progress

[wurlycorner]

Right, some progress...
Thanks to the above discussion (all the detail in that thread) I have got Lexia talking to the car (partially).
First result was this;

NO FAULTS? WTF? You've had the bloody Engine management fault light permanently on for ages!

Anyway, I ploughed on going into the injection diagnostics;


Yes, well done, that's my car

Identification;

Interesting...

Read faults;



Into this then, to see if that sheds any light;





I've no data to go on, but I thought the ignition advance looked a bit excessive?

Anyway, the screen then crashed out (said connection to ECU lost).

Next up, to run through the test options it gives you (limited on this ECU)...


Great

Nothing worked from then on. I rebooted Lexia, turned the car off and on, no change.
Wiggled the leads around where they connect into the PCI unit and found the RS232 plug ever so slightly loose... Tightened it up et voila!
Suddenly we have logged faults!

And the best thing? It confirmed my suspicion all along that it was probably a knock sensor fault!

Anyway, I ran through the rest of the tests;


All checked out ok. The injectors are really quiet though, took a lot of very careful listening - I was sure one wasn't working, so resistance checked them (all ok at 16ohm) and re-tested several times before I managed to hear the last one (difficult to get ear close up to that particular one).

So... Knock sensor. Difficult thing to test. All the wiring visibly looks intact. I'll bell it out back to the injection ECU and if that's ok, change the sensor. Hopefully that will be the end of it...

[CitroJim]

The knock sensor is delicate Iain, it's a crystal microphone that literally listens for a knock... It will measure O/C on a continuity check. They hardly ever fail either...

[wurlycorner]

Yep, I know - they're a PITA to test. (Although having said that, the last one I had to replace was a pretty conclusive fault... I'd chopped through the flying lead with an angle grinder! )

I assume the Xantia one is the modern type which can only be tested 'real world' with the engine running and forced to pink??? (as opposed to old ones that were a bit more crude and could be tested by being 'tapped' with any old random stuff)

I did a quick continuity and earth test just to check there was nothing silly going on (you never know) and all came back o/c as it should.

Pain to find on service.citroen, but eventually found it (NFP at Citroen (as expected) but readily available elsewhere).

[CitroJim]

Item 7 in the above picture has a habit of splitting and admitting air Iain, worth checking for the misfire...

[wurlycorner]

Big update...

I have it!



Unfortunately not fitted as planned, due to having other Citroen priorities


Anyone know the correct torque setting please?
I can't lay my hands on the Haynes manual at, and it's not listed in Russek.

[wurlycorner]

Went out to fit the knock sensor today, in the rain (dedication )

Access doesn't look too difficult, because it's on the front of the engine and you can get your hands to the sensor and see it without stripping anything down, but getting a tool to it is a bit of a PITA, as it turns out. It's a 13mm bolt.

I eventually settled on moving the HT leads for the middle 2 plugs out of the way and unclipping the injection loom, removing associated clips and moving it to one side, then I could get a small socket set down to it, from behind the fuel rail;



(that's the head of the ratchet in place on the bolt, lit up)

And looking down from the top of the engine, towards the front of the car;


Old sensor (right) and new sensor (left);

The eagle eyed (not really!) of you will notice that the new sensor has a longer cable on it. That's a paint, because it might prove a bit difficult to lose the extra without it snagging on something, but we'll see...

After market part number;


So, just a few minutes work left and then to fire it up, all fixed, right?

Well, having removed the sensor I could see a loom running across the front of the engine, touching the front of the block. Thought it best to check the condition of the back of the loom, in case it had chaffed... Pulled it forward and the conduit had hardly chaffed at all, definitely not a concern, but...

The flexi conduit was absolutely brittle as and crumbled away when touched.



Looks to be the positive lead to the starter and/or alternator, so definitely no-way I could leave it like that! Unfortunately I didn't have any split flexi conduit the right size and the smallest stuff the DIY places open today stock, is 20mm, which is way too big, so that's it for the day.

So glad I stood out in the rain to do that

Never mind, it's another step closer

[CitroJim]

Good call on the loom Iain...

So has the new knock sensor helped?

[wurlycorner]

Don't know - I'd have to remove the sensor again to replace that conduit, so I've left it like that till I've bought some conduit the right size.

[HansNOR]

whaat. u leave the readers hanging with a "to be continued" - here i was reading all excited waiting for the "hooray"

[wurlycorner]

'fraid so... You'll just have to wait it out a bit more!

[superloopy]

Me too

[CitroJim]

Gives us all something to look forward to!!!

[superloopy]

As if the new upcoming year wasn't enough ...

Sent from my LG-D855 using Tapatalk

[wurlycorner]

Right, so last weekend, as well as the C5, I also did some stuff on the Xantia.

Unpicked that wire with the knackered copex covering. It was indeed as thought, direct positive feed to the alternator or starter motor... In fact, it was both!

Runs in one length back over the gearbox to the main positive loom;

I got the old copex off and the new copex on, without opening the cable clip sat on top of the box (bound to have broken if I tried).

I found another fire waiting to happen on this loom, at the other end - the insulation around the crimp at the alternator had gone brittle and broken up. It was rubbing on the chassis of the alternator (see the small shiny area to the right of the bolt in this pic!) but fortunately still had a piece of insulation in between for now;


Starter motor terminal is a bit of a PITA to get at;


This is the terminal that goes onto it, half way along the loom. Pretty gash IMO tbh, but normal for modern cars



All wrapped up and back in place. Don't you just love these short days, working in the dark...


I was able to slip the alternator end crimp terminal out and back through the loom tie there, without having to cut it off;


And a shot of the area that had started it all in the first place - much better now


Finished off re-assembling everything and ran the car up.
Definitely runs better. Still not 100% sure it's right, but the thing hasn't had a proper run to clear it out for about 5 years, so we'll see what happens when that day comes!!!

Annoyingly the new knock sensor plug doesn't have the moulding slots needed to attach it to the loom clip I'll need to find some decent neat way of doing it - just lashing a cable tie round it will annoy me intensely.


So now... Onto another ABS sensor and then finally back to where I was about a year ago, when it just needed a CV joint gaitor and setting up the suspension.

Progress!

[CitroJim]

Getting there Iain... Another year should see it on the road!

Then you'll have to come and see me for a good once-over inspection of the car!