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CLIO 1.5 DCI CUTTING OUT, FUEL PRESSURE GOES TO MAX
have a renault clio 1.5 dci, 2004, 82hp with delphi high pressure pump. The problem is that the car just cut out. The fuel pressure regulator was change month ago and was fine till now. Now it wont start at all. Using delphi tester get the code df127---sensor supply voltage, below minimum limit, permanent. Till now was always intermitent.
What is interesting is that when I put igniton on, the car is cold and has been staying for more than 24 hours and the pressure in the fuel rail is 2000 bar. Fuel pressure sensor has 5,01 V. This is seen on the tester.
I have measured fuel rail sensor connector and get 5v reference. Ground is ok. And signal is 0,5v. I tried to cranc a little bit and pressure than drop and rise again to 2000.
Any idea what to check and how?
One general question: Accelerator pedal position sensor has 6 contacts. Is this ref, sig, ground and ref. signal, ground. How to test this? Have measured the resistance of all this 6 wires from the connector ecu and accelerator pedal position sensor connector and get: 2, 0.2, 0.2 and 0.4, 0.5, 1.5 ohm. How to explain this data? Is useful to do this way?
Already has been done: (cleaned reservoair, new fuel filter, new egr).
We don't have this vehicle in the states so I can't comment specifically but seems to me as though your fuel pressure pressure sensor wiring is shorted to power or your sensor is bad there is no way you can have 2000bar after vehicle sits for 24 hours! You say you checked sensor and have 5v ref ground and 0.5v on signal wire? Or 5v on signal wire? Is this sensor connected or disconnected?
Your fuel rail pressure sensor signal wire is what will tell your ecu what pressure is in the rail, 0.5v KOEO is totally normal, equates to zero pressure, I very much doubt there is 2000 bar actually in the rail,especially if rail pressure sensor shows 0.5v KOEO ,when you turn the car off the fuel pressure control valve immediately opens to release pressure in the rail so that the timing belt/chain doesn't have to turn a fully pressurised high pressure pump on next start up.
If I'm not mistaken, I have seen these cars do similar things with a weak battery in the past, worth checking before you dive too deep into it
Try checking with another tester. You should also do injector leakdown test, because code df127 often sets, when injector is faulty. I have diagnosed several of them with df127 code and it is always been leaking injector.
Also scope injector voltage (whether the signal exists) and fuel pressure sensor signal to see how they work,
Hi,
thanks for suggestions.
For now I have measures the disconnected connector of fuel sensor. What comes from ecu.
Also thought it might be battery and fuse corossion. Have cleaned all an also put other battery but the same.
Found the repair manual for this car and for this error it is written to check all the sensors.
So today I have removed front bumper to check the air conditon pressure switch which is also connected to ecu. It has 3 pin connector. I do not know how to explain the results I get:
Ignition was on and connector disconnected. Using multimeter I put ground on the battery and than get on one pin: 0,013V, second: 5,03v, third: 4,85V. This time I also put connector on switch and get on one 0,01, on two: 5,03v, on three: 0,66v.
Did not test the ground. But I am confused. 5,03v should be reference voltage, 0,013v seems to be ground. Why is there also one wire with 4,85v coming on connector???
I measured if this wires from connector reach the ecu and yes they come to it and the resistance of all is 0,3 ohm.
Can someone tell me how to test if this 3 wires are maybe somewhere come in connection with each other?
I think there must be a problem with this wiring at one of the sensors because I checked with tester what is the situation and you wont believe no errors, car started and work with no problem. Of course it is not repaired....
I was heppy when error become permanent that will be easier to find it out...
I started with aircondition because in past also when aircondition was off it was heard this clicking sound when you turn it on.
There is one more wire that goes to aircondition compressor-what is this for.
Which wires should be checked if the aircondition was kicking on and off by its own.
thanks for help,
Borut
