All Things V6...

[DHallworth]

Well I guess I've had my theory of "Petrol going stale is a myth" tonight...

I took the electric pump out of the tank and pump a hand pump and hose into the tank and sucked out the remains. The petrol I've taken out smells stale but the biggest difference is in the colour!

On the left is fresh petrol, on the right is what I've taken out of the C5.





Before I took the Xantia V6 off the road a few weeks ago I necked it with fresh fuel for the C5 so I'll whip it out and get some fresh stuff in the C5 tomorrow. I also took the crankshaft sensor out of the C5 tonight and gave it a good clean (not that it was dirty) I also noticed that the two wires going into the plug were slightly damaged. There was some copper showing through the insulation so I've wrapped them with insulation tape tonight to ensure that they aren't arcing.

Will report back as I find out more.

David.

[CitroJim]

Interesting to show old and new petrol side-by-side David. I'm rather worried to see it so close to a used ashtray though

I would think, speaking of the GPS CD, that the system has copy protection. I know the old Lexia 2 did and however you tried to copy a Lexia2 disk, even as an ISO, it just wouldn't play so I'd not be surprised if this was the same.

The trader was likely shut down because everyone had this issue..

Hope the new petrol does the trick!

[DHallworth]

Jim, I don't smoke and tbh didn't notice the ash tray until the pictures were online! Ho Hum...

Right, there's 40 litres of fresh petrol in the tank, I've disconnected the feed at the injection rail and flushed it through until it was fresh stuff coming through to the rail.

I've been trying to start it today with the airbox off as I was at the crank sensor wiring last night and you can hear it popping in the intake. Like small back fires but they only happen when it's spluttering, not all the time whilst trying to start it. Also when it's spluttering there's smoke coming from the exhaust that stinks of petrol so I'm guessing it's filling the exhaust with unburnt fuel.

Am just in the process of doing a BSI reset on it and we'll see what happens afterwards.

David.

[DHallworth]

Right, just graphed some readings and there's some interesting things going on here...

Occasionally whilst cranking the vehicle speeds sensors record a speed of around 14kph momentarily then drop back to 0.

When checking the gearbox ECU things start to get clearer...

The engine speed sits at zero, the engine torque sits at -100, and the gearbox input sits at zero.

When cranking the engine speeds spends most of it's time sitting at zero then when it does detect an engine speed the car splutters and tries to start. Occasionally the gearbox input will get a reading and the engine speed is still at zero.

I've disconnected, cleaned and reconnected the plugs on the top of the gearbox but this hasn't made any difference. I think I need to try and work out how the gearbox ECU detects the engine speed. My guess is that it uses the CANBUS system to get it's reading from the engine ECU. If this is the case I need to try and find out why it's only getting a reading intermittently. I tried unplugging the gearbox ECU but that sent every other ECU on the car ballistic and it didn't even cough whilst that was unplugged.

I really need to try and get my SEDRE working so I can get into this thing.

David.

[Mandrake]

Any spark ? (Sorry to sound like a broken record )

The reason I suggest checking that is because the gearbox gets the engine speed from the engine ECU, which in turn gets it from the crank sensor. A faulty crank sensor sensor signal would give no spark, no start, as well as no engine speed reading at the gearbox so fits all the symptoms. What gap did you set the crank sensor to when you refitted it ?

You really do need to check the basics eg spark and fuel pressure first before you spend hours delving into the intricacies of the CAN bus, communication between ECU's etc. While the data from the gearbox is useful, lack of communication between the gearbox and engine will not prevent it starting, otherwise the gearbox limp home mode wouldn't work!

Some of the readings you're getting from the Lexia are nonsensical, like the engine torque of -100 so they could be red herrings that will lead you around in circles...and you have too many fault codes occurring at once to be certain where the problem lies.

I'm sure compressions will be fine so check fuel pressure and spark first so we will the have some idea of where to investigate

[DHallworth]

Cheers Simon.

How do you check spark on these? Just lift the plug out and attach it to the coil and earth it onto the rocker cover? Will need to try and get a new fuel pressure gauge as mine has perished unfortunately.

The crank sensor on these just sits in a hole on top of the bell housing, there's no way of adjusting the gaps. It's also the most awkward little sod to get at too!

David.

[Ben82]

I really need to try and get my SEDRE working so I can get into this thing.

As per usual let me know what diagrams you want, and I'll try my best to find them

Got the 4HP20 one as a PDF that I'll pop you over a link to in a PM.

[Mandrake]

The ES9J4S is coil over plug with 6 coils (not 3 like the ES9J4) I'm not sure if they're physically individual or come in two 3 coil packs (Ben ?) but you should be able to lift one out and hold the tip that normally presses into the spark plug close to the engine chassis, a good spark should be able to jump up to 20mm.

If necessary poke some wire down the hole that normally goes to the spark plug and let the other end sit 10-20mm from the engine chassis.

[Ben82]

The ES9J4S is coil over plug with 6 coils (not 3 like the ES9J4) I'm not sure if they're physically individual or come in two 3 coil packs (Ben ?).

No coil packs, just 6 individual coils

[DHallworth]

Will give that a go later and see how we go.

I'm fairly certain that I'm getting a different reading of engine speed in the parameter measurements on the gearbox ECU to what I am on the engine ECU which is why I wasn't leaning towards a faulty crank sensor or anything like that.

Will see how we get on later and go from there. Am off for some kip now as I was on call last night and spent most of the night working hence being off today.

David.

[Mandrake]

The ES9J4S is coil over plug with 6 coils (not 3 like the ES9J4) I'm not sure if they're physically individual or come in two 3 coil packs (Ben ?).

No coil packs, just 6 individual coils

Ah, perfect Much easier to diagnose than a coil pack waste spark system like the ES9J4 where its physically very awkward to test the spark of an individual cylinder...(since testing any of the front cylinders means lifting the whole coil pack out and running extension leads to the plugs...)

[Ben82]

David,
Just had a thought on the coils. I remember reading some of the older ES9J4S' had Sagem coils, and at some point they were updated to Delphi coils. Think the easiest way to check is the Delphi ones apparently have white tops. If you're fiddling about with them, probably worth checking you have the Delphi ones (the Sagem ones were prone to failure).

Ben

[CitroJim]

ES9J4 ones are Sagem also and just as prone to failure. Always to have a spare set on hand...

David, it really does look like sensors are doing strange things. It's an odd one...

[Mandrake]

Looking at the state of that petrol is it possible that its clogged up the injectors ? Popping in the inlet manifold when trying to start suggests its running very lean...

Perhaps it started ok the first time because the petrol in the fuel lines was of good quality (the volatile parts of the petrol would evaporate over several years in the tank but not in the lines) but it then drew in the deteriorated fuel then after being turned off and sitting for a while it gunked the injectors up.

If its a fuel problem you could try injecting some propane or butane (or carb clean) into the inlet manifold (or disconnect the vacuum hose to the brake booster and inject it to the manifold that way) while starting and see if it tries to kick over or starts.

If it does you know you've either got a fuel pressure problem or the injectors are blocked or not being fired, if the propane/butane makes no difference head in the direction of no spark instead...

[DHallworth]

At the moment the C5 has taken a bit of a back seat. I'm in the middle of fitting a polybush kit to our Freelander V6 which is turning out to be a miserable job given the number of bushes on the bloody thing!

David.