XANTIA HDi RUNNING ROUGH

[Skull]

What is this talk about hard stalls?

Hard stall - is the term I used to describe a sudden and violent stall of the engine when the clutch pedal is already released and you are just driving along merrily when without any warning or slow loss of power (no warning) engine shuts off suddenly!

If your car pulled onto the drive fine then a jumped tooth is unlikely…..

Unlikely but it’s moved either because of jumping a tooth OR as Jim has suggested the Woodruff key being damaged….

[Skull]

Thanks Rothgear

… Have you messed around with any of the connectors to the two solenoids in the top left corner of the engine bay.

Jim tested those whilst checking EGR valve….

[Rhothgar]

What is this talk about hard stalls?

Hard stall - is the term I used to describe a sudden and violent stall of the engine when the clutch pedal is already released and you are just driving along merrily when without any warning or slow loss of power (no warning) engine shuts off suddenly!

If your car pulled onto the drive fine then a jumped tooth is unlikely…..

Unlikely but it’s moved either because of jumping a tooth OR as Jim has suggested the Woodruff key being damaged….

Are you saying therefore that the engine was cutting out?

If so, according to Fault Code 3 in the manual, one reason can be diesel injector return flow too high.

Pin 1 of CTS goes to Pin 46 at ECU. Pin 2 of coolant temp sensor goes back to Pin 45 of the ECU. Unlikely that you will have done damage because the power probably comes from the ECU and depending on how much returns will indicate to engine what the temperature is.

[Skull]

Are you saying therefore that the engine was cutting out?

If so, according to Fault Code 3 in the manual, one reason can be diesel injector return flow too high.

Yes cut out immediately - no warning

[CitroJim]

The solenoid codes may well be relevant. Have you messed around with any of the connectors to the two solenoids in the top left corner of the engine bay. Switching them around can cause issues. I did that once. In fact, I ended up having to buy a replacement on Amazon but I was getting an intermittent boost fault. Forget the code now.

All faults as a result of planned disconnections during testing Roger.

They all cleared and I left the ECU showing no faults of any kind

This problem very unlikely to be ECU related or electrical in my view.

[Rhothgar]

Skull.

I think if you do your own spannering the first thing to check is the woodruff key as per Jim’s suggestion as a first off especially if you are not elecTrickery savvy. I note he says camshaft but I am wondering why he has come to that conclusion.

Could the woodruff on the crankshaft have sheared?

Do you have the kit for locking off the flywheel etceteras?

When I changed the cambelt in mine last year, I mistakenly rotated the belt tensioner in the wrong direction. It was after midnight in my defence. Then I drove home once back together.

The next morning I noticed that the cambelt was loose. Even during the 10 mile drive home it hadn’t skipped a tooth. It must have worked loose during the journey. A lucky escape.

I cannot recall if this engine is interference fit. The suggestion from the theories from Jim et al is that it is if they are suggesting valve issues.

[Rhothgar]

The only way you will have damaged the ECU is if wire is 12V and you bridged that. Please check the voltages as per my diagnostics PDF.

[Stickyfinger]

Could the woodruff on the crankshaft have sheared?

On my (now sold) 2.1XM the cam shaft pulley spokes were shattered as well as a sheared woodruff keys on both ends (egr vac-pump is on the other end) due to a "hard stop"........the belt is certainly strong enough to allow some serious damage to the top end.....

[Skull]

Cheers Jim and Rothgar for clarification,

Seems to be a mechanical issue rather than a sensor but when I bridged the coolant temperature sensor it was 5v (mentioned earlier in post ^)

I have the tools just lacking my ElecTrickery certificate

[Rhothgar]

Cheers Jim and Rothgar for clarification,

Seems to be a mechanical issue rather than a sensor but when I bridged the coolant temperature sensor it was 5v (mentioned earlier in post ^)

I have the tools just lacking my ElecTrickery certificate

Noted but…
we need to be sure that wire 3 is a signal wire to the fans which i am sure it must be but I’ve not had time to check.

I imagine that once the temp sensor warms up, the 5V being supplied by the ECU at pin 1 is routed through pin 2 which then increases in voltage (usually they decrease from what I briefly read - depends on whether temp sensor is PTC or NTC). This is how the ECU determines what temp the engine is at.

Pin 3 may also work similarly in that once it warms that sends a signal to the ECU to switch the fans on or perhaps provide the earth?

You did say, I guess that there was no voltage at pin 3. What you didn’t say was whether the connector was connected or disconnected and whether you bridged the terminals from the connector. It would obviously make a difference if you bridge a connector by back probing it whilst still connected AND whether the ECU connector was connected or disconnected.

I always ensure things are disconnected if I am testing the load carrying capacity of the wire to prevent potential damage.

[Skull]

So when I unplugged the blue sensor plug, initially just the passenger side cooling fan started running high speed, my Haynes manual covers the 2.0 HDi as well as other previous models and is quite dis-jointed.

Pin 1 5v
Pin 2 Neg
Pin 3 Neg

I shorted Pin 1 and 2 - no effect
I shorted Pin 1 and 3 - both cooling fans ran low speed

I reconnected the blue plug and the engine started running a lot poorer after about 5 seconds both fans slowed and stopped at the same rate.

So the fan motors do work, coming on around 95 degree C on the vehicle gauge (I'm still in the rabbit hole though).

Rothgar those voltages were with the plug disconnected from CTS but connected at ECU.

I didn’t back probe anything.

[Rhothgar]

So when I unplugged the blue sensor plug, initially just the passenger side cooling fan started running high speed, my Haynes manual covers the 2.0 HDi as well as other previous models and is quite dis-jointed.

Pin 1 5v
Pin 2 Neg
Pin 3 Neg

I shorted Pin 1 and 2 - no effect
I shorted Pin 1 and 3 - both cooling fans ran low speed

I reconnected the blue plug and the engine started running a lot poorer after about 5 seconds both fans slowed and stopped at the same rate.

So the fan motors do work, coming on around 95 degree C on the vehicle gauge (I'm still in the rabbit hole though).

Rothgar those voltages were with the plug disconnected from CTS but connected at ECU.

I didn’t back probe anything.

Thank you for clarifying.

Can you recall what your reasoning was for bridging the pins together?

[Rhothgar]

OK. I’ve found it. Wire 3 goes to the dash and presumably either moves the temp gauge and/or brings on the red warning led.

[Skull]

.

Can you recall what your reasoning was for bridging the pins together?

Because it was taking ages for the engine to warm up, the red light (coolant level) within the temperature gauge and STOP were illuminated - I expected the fans to run at that stage so wanted to prove that both motor/s were working…

[Huskyxantia]

Seems your getting somewhere , even though its like stabbing in the dark,ive subscribed to this post I'm keen to find out what happens.