'96 Xantia Activa - back to the future!

[wurlycorner]

And I forgot about the ABS fault that's appeared and the blowing exhaust...

ABS fault is (the other) rear ABS sensor. This is what turned into a whole load of pain and made me give up last time Hopefully won't be the case this time though, because I've had at least some of that side already in bits
Exhaust back box has to come out for this one though but at least it's the same joint that's blowing so 2 birds an' all that
Couldn't get a bloody sensor this morning though, so that's another week lost

[wurlycorner]

Ok, so with the C5 driveshafts sorted and the trailer fixed, this is next in line for the ramp.
For the MOT, it needs;
- CV gaitor
- ANOTHER ABS sensor
- Leaking exhaust joint sorting
- Full suspension set up (level and roll) which will hopefully sort the hard rear end (oo-err)

It also now needs a rear tyre I think. Noticed one of the Michelin's has cracked up badly around the tread line

So, battery back in last weekend and run it up with the intention of loading it on the trailer and taking over to the barn. I'd forgotten that it was running on 3 cylinders.
Left it in in disgrace and thought I'd try to use the Lexia this weekend to work out what was going on.
Plugged it all in, arsed about and... it just won't talk to the car at all - doesn't recognise any ECU's This may well be something I haven't set up right, or it might be the car (hopefully the former, although this one has always steadfastly refused to talk to any aftermarket diagnostic kit).
So old skool diagnostics then...


Actually running on 2 cylinders, not 3, then
(the middle 2 were soaked in fuel, I assume the outer 2 are sooty black because it's running so rich trying to compensate and keep the engine running)
Cleaned them up and refitted;


From memory (not rechecked yet) I think it's a 'lost spark' type ignition, so it's a simple twin coil pack, with the centre plugs running off one coil and the outer plugs running off another. So hopefully it just needs a new coil to sort this.

Also, hopefully that will also explain why I thought it was 'hesitant' and 'bogged down' a bit when putting my foot down when the car was last on the road (it was running on all 4 then, but felt like the timing was wrong). My hypothesis is that the coil would have been on the way out, causing that problem.

Well, lets hope so, anyway...

[mercutio]

certainly looks like nice easy fix

[wurlycorner]

Update...
It's not an easy fix.
Not just because one of the coil bolts was corroded into the head, but because... Changing the coil last night didn't fix it
(There is a big difference in resistance in the coils though - old coil was 12k ohm across the HT side of each coil, new one is 7k ohm across the HT side of each coil)
I'll have to dig out the wiring diagrams now to suss out what else it could be.

[vanzep]

gotta say id did like the suspension on the xantia volcane - inspired a lot of confidence in the twistys
mind u it was a hire car i had for the day many many moons ago so maybe thats why i enjoyed it so much

[wurlycorner]

Detective work commences...

Consulting the wiring diagram;


1105 is the Ignition Module
1135 is the Ignition Coil
1136 is the Ignition Coil Capacitor

They're the only things that can be at fault as far as I can see (aside from the ECU of course).
(1304 is the fuel injection relay which is also part of the circuit, but that must be working otherwise it wouldn't be running on even 2 cylinders).

1135 has been changed and the old one has actually all belled out ok anyway (although as I said, the HT side of the coil is much higher resistance at 13k Ohm than the replacement is, at 7k Ohm).
I can't actually see how 1136 could cause it to run on 2 cylinders (if the capacitor had gone dead short it would just drag down the whole ignition/injection circuit, if it had gone open circuit or changed capacitance it would just mean there was noise on the circuit which would result in rough running or such-like).
So I'm assuming it must really be 1105 (or the ECU), or the wiring/connections at those.

My next steps then, are to bell out the individual wires and to check the terminals are ok (I don't have the circuit internals of the Ignition Module, so can't check that really).

I'm assuming this is the Ignition Module (1105);


Currently have no idea where the Ignition Coil Capacitor (1136) is, but hoping someone on the FCF can advise or at worst I'll have to trace back that wire (which disappears off down one side of the engine )...

[wurlycorner]

Ok, progress!

So belling out from the LT side of the coil, all seemed ok. The Ignition Coil Capacitor is potentially u/s (difficult things to test without a capacitance meter, but on a resistance checking multimeter you can normally see them charging up and this was doing nothing) but that's a minor issue and I can follow that up later.

It did show up a couple of poor looking connections at the Ignition Module;


Haven't photographed great, but there is verdigris on pins 4 and 7. Didn't seem to affect the resistance readings but I cleaned them up with electro clean spray and scraping at them with a watch makers screwdriver.

So next up was belling out the remaining pins from the Ignition Module connector. Again, all were fine. Spotted a split in the connector to the Fuel Injection Relay which isn't great, but isn't causing a problem and the relay is well protected inside the ECU box;



So nothing conclusive...

I don't have the internal circuit for the Ignition Module so testing it was a bit of guess work, but seemed a pretty safe assumption that the 2 inputs from the ECU were the firing signals for each of the 2 coils. Pin 4 is earth, so resistance checking between pin 2 and 4 and then 7 and 4, should give the same...
4 and 2 was about 2.6k Ohm, 4 and 7 was over 30k Ohm Didn't sound right...
So I whipped it off for a closer look, on the basis it was going to be knackered and I'd need to change it anyway;




Connections were pretty dull looking. I'd already given them a good spray over with electro clean but obviously not achieved much. Scratching away at pin 7 with the multimeter caused the resistance to drop to 2.6k Ohm (same as the other side)
Gave all the pins a good scratch over with the screw driver to clean them up. Looks like they have some kind of electro plate coating on them, which has badly tarnished. It wouldn't clean up, so I scratched it off.



Plugged everything back in...

Sorted Sweetest it's ever run that I can remember

It did start occasionally misfiring when it was revved up (something it's done for a long time before finally crapping out onto 2 cylinders) so I don't think it's a long term fix with the pins and I'll have to replace the module.

It makes sense really - that's the side of the rad that was leaking (steam) when hot, so it's probably made its way into the connector and tarnished the pins.

Eurocarparts do a new module for around £35. It's not an OEM Bosch one though, so I'll have a dig around to see if what price they are before making my mind up which one to buy.

[Vtecmec]

Nice, love the steptoe gloves.

[wurlycorner]

If you like the gloves, you should see the trousers!

[wurlycorner]

Update...

So much for spending a day in the sunshine sorting this, instead of a day inside at the barn making progress on a 3g lude...

The key is in the ignition, the drivers door lock is up, but I am outside the car and it won't let me in.

drokking thing