110 Hdi Fuel Rail Pressure Sensor circuit - P0190 fault

[Springnuts]

Good morning all.

Well, our 110Hdi engine management light came on, and the power drops out at 2500rpm - though it will get up to 75mph or so (in due course) and runs smoothly - maybe a little lumpy at idle. Car has 226k miles. High Pressure Fuel Pump was replaced at 181k miles - I don't know if the new pump will have come with a new Fuel Rail Pressure Sensor or not.

I have a cheap OBDII reader which gives the fault: P0190: Fuel Rail Pressure Sensor Circuit Malfunction. I have found the sensor (on the end of the fuel rail; black plastic connector) and can see the start of its wiring Nothing obviously wrong. I found a post suggesting the wiring here is a short section only; three core, leading to a plug on the main wiring loom. I imagine that the sensor itself may be the problem (in which case it needs replacing). If the sensor is OK but the wiring is faulty my hope is that I can remove this short wiring section and check it for continuity, hoping to find a break which I can repair.

Some questions please:

Q: Is there any trick to unplgging the wiring from the sensor, which is, I gather, an expensive and no doubt (given its age) fragile piece of kit?

Q: Once unplugged Is it then possible to check the fuel pressure sensor and the wiring to see where the fault lies? I have a basic volt and resistance meter.

Q: Can anyone tell me where the wiring is routed after it leaves the sensor - or at least where it ends (so that if the section is faulty I can bypass it)?

Q: Does ayone have any other experience of this fault and how it is resolved?

Thanks in advance people!

Springnuts.

[Springnuts]

I am away for a few days - in the meantime - any ideas welcome!

Springnuts.

[Springnuts]

Hi - anyone got any ideas on this please?

Springnuts.

[Springnuts]

OK _ I understand there should be 5v in one line, and a good earth in one other. Third is signal.

[Bailes1992]

Take it out and clean it. You may need to replace it though.

[mattyf]

I've got the same error on mine.
1. How do I get to it?
2. Clean it with what??

Thanks,

matt

[Springnuts]

Sadly our 406 has gone to Pug Heaven. The engine light was still glowing as it passed over ...