[fatman.portugal]

Engine check comes on, Immobiliser indicator light on, car stops dead. Wait 1 hour and the car starts but engine check stays on. drives but cuts out intermittently. ODBll scan shows U0003 and U0004 codes.

I can't find a solution or decent explanation for these codes other than "CANBUS Communication Problems"

Any help would be greatly appreciated.

 

[AUTOSPARK]

I wouldn't worry too much about those codes. CAN problems shouldn't cause the engine to quit, and shouldn't prevent it from restarting when it does.

What you describe sounds to me more like a crank position sensor fault. These sensors are known to fail when the engine heats up, causing the engine to quit. The engine then isn't able to restart right away. You need to wait until the engine, and the sensor, cool down. Then the sensor starts to work again, allowing the engine to start.

I assume your car is fitted with the 3 cylinder engine. If so you can confirm that the crank sensor is the cause of the problem by checking to see if the electric fuel pump is being switched on DURING CRANK when the engine wont start. The ECU wont switch the pump on if it's not getting a good signal from the crank position sensor. There is a fuel pump check terminal on the engine bay fusebox specifically for that purpose. Look for "F/P CHK" on the diagram on the fusebox cover. Connect a voltmeter to the pump check terminal and check to see if there is 10V being supplied to the terminal while the engine is cranking over. If there is no voltage when the engine wont start I think you can feel pretty confident that the crank position sensor is the cause of the problem.

If I helped you fix it, why not...

Your support is greatly appreciated​

 

[fatman.portugal]

Thank you so much for that. I had started to suspect that but was now doubting myself... All I need now, is to know where that silly thing is on the engine? I have looked, but can't find it.

 

[AUTOSPARK]

All I need now, is to know where that silly thing is on the engine?

On the back of the engine block...

If I helped you fix it, why not...

Your support is greatly appreciated​

 

[fatman.portugal]

Thank you so much for that. I'll pull it out today and order a new one. I'll post back here just for information.

 

[fatman.portugal]

Hi Autospark. Thank you for your help before and boy, was that difficult to replace! My hands are just too big! I am hoping I can ask for some more help?
Now, with the Crank Position Sensor replaced (Ridex), the engine cranks but refuses to start. (Before, it started instantly but ran for around 10 minutes then cut and wait 30 minutes to start)
I tested;
Fuel pump runs for 2 seconds when ignition goes on and shows 10Volt on the pump test lug when I crank it.
Fuel rail gets fuel from the fuel pump and Injector pump, pumps through fuel when I crank it.
However, with the little overflow/bleed pipes removed from the injectors, no fuel comes out when I crank or when I turn the ignition on?
Also, now the Key/Immobilizer light no longer lights up when I turn on the ignition, or when I crank it...
The red fuel filter light stays on and I don't remember what it used to do before?
I would be most grateful if you could tell me what you think.
Gerard

 

[fatman.portugal]

On the back of the engine block...
View attachment 471617

If I helped you fix it, why not...

Your support is greatly appreciated​

All done, but now...

Now, with the Crank Position Sensor replaced (Ridex), the engine cranks but refuses to start. (Before, it started instantly but ran for around 10 minutes then cut and wait 30 minutes to start)
I tested;
Fuel pump runs for 2 seconds when ignition goes on and shows 10Volt on the pump test lug when I crank it.
Fuel rail gets fuel from the fuel pump and Injector pump, pumps through fuel when I crank it.
However, with the little overflow/bleed pipes removed from the injectors, no fuel comes out when I crank or when I turn the ignition on?
Also, now the Key/Immobilizer light no longer lights up when I turn on the ignition, or when I crank it...
The red fuel filter light stays on and I don't remember what it used to do before?
I would be most grateful if you could tell me what you think.
Gerard

 

[AUTOSPARK]

Also, now the Key/Immobilizer light no longer lights up when I turn on the ignition, or when I crank it...

The immobiliser light not coming on usually means the ECU is unable to read the key's transponder signal, which will prevent the ECU from injecting fuel into the cylinders. More often than the cause of that is high resistance in the connector between the immobiliser ring antenna and the key signal amplifier module (SMARTRA). The key signal voltage is very low and it is easily dropped to nothing by the resistance in the connector. The fix is quite simple. Just cut the ring antenna wires off both sides of the connector and solder them together. Removing the connector removes the high resistance and allows the key signals to pass again. Below are some photos I took the last time I had to do this repair.

If I helped you fix it, why not...

Your support is greatly appreciated​