Won't Start...

[H Peasource]

Can't give you a definite answer but I agree with your understanding of how most common rail pumps regulate pressure. The valve is very likely to be part of the pump.

That said I suspect that the valve itself is not your problem. It's far more likely to be a problem with the wiring. In your position I'd be checking the wiring carefully for any chafing/breaks, checking for any loose pins/sockets and tightening them up and then cleaning everything with a good contact cleaner followed by some silicon contact lubricant.

Alan

 

[Jon_G]

Can't give you a definite answer but I agree with your understanding of how most common rail pumps regulate pressure. The valve is very likely to be part of the pump.

That said I suspect that the valve itself is not your problem. It's far more likely to be a problem with the wiring. In your position I'd be checking the wiring carefully for any chafing/breaks, checking for any loose pins/sockets and tightening them up and then cleaning everything with a good contact cleaner followed by some silicon contact lubricant.

Alan

Hi Alan - I'm beginning to think that there's a short somewhere in the loom and your suggestion here is probably the best course of action. Otherwise I guess the short (to positive, oddly) must be inside the ECU?

Thanks,
Jon

 

[CJM]

Hi Jon,

Sounds like you have got it going.

P1059
Fuel Rail Pressure Control Valve Circuit Open

Probably due to a loose connection after doing all the work previously, apart from the MAF sensor, did anything else feel slightly loose?

 

[Jon_G]

Hi Jon,

Sounds like you have got it going.

P1059
Fuel Rail Pressure Control Valve Circuit Open

Probably due to a loose connection after doing all the work previously, apart from the MAF sensor, did anything else feel slightly loose?

Hi Carl - Yes, I've got it going, I don't like to claim that I was responsible for a proper repair. For all I know it could stop any time, so I haven't been very far in it.

When I pull the electrical connector off the pressure control valve (making it open circuit) I get a P1057 - so the P1059 must be something else (shorted to power has been suggested previously on this thread and elsewhere). Where are you getting your code info from?

It is looking more and more that it could be a wiring issue, which I have to consider might be in the ECU itself. All other connections under the bonnet (except the MAF plug) look and feel fine. When it's running, I'm going around shaking connectors and looms to try to induce the problem. Nothing yet, but I need to start doing the same thing behind the dash. Do you know where the ECU is?

Thanks,
Jon

 

[H Peasource]

Jon,

I think you are worrying yourself unnecessarily about the ECU. This just does not sound like and ECU fault - they tend to be either permanent or heat-related. My money is still on the connector between the loom and the valve. I know you've looked a this but how closely? It's really a magnifying glass and bright light to be sure. Also don't forget to examine closely where the loom wires enter the plug socket - a classic area for wire breaks or water entering the connector.

Alan