funkmonkey66
Guest
Ok plugged my laptop into the car today to play a bit if fault code bingo and to my surprise I'm down to one code now, 17655 - needle lift sensor (g80): open or short to plus. Simple question really - what's that mean then?
-
Hey Guest one of our sponsors Progressive Parts is running Black Friday and Cyber Monday offers - more details here
Maybe need to replace the sensor, heres the detail about it from the TDI Tech doc :-
The injector of the 3rd cylinder is equipped with a needle lift sender (G80) for registering
the point of commencement of injection.
The sender signals the actual opening time of the injector to the control unit. This
signal provides the control unit with feedback on whether the point of commencement
of fuel injection conforms to the map.
Function
Needle lift sender G80 is a solenoid and is supplied with a constant current by the control unit. This produces a magnetic field. A pressure pin inside the solenoid forms an extension to the end of the injector needle. The movement of the injector needle alters the magnetic field and causes distortion of the DC voltage applied to the solenoid.
The control unit calculates the actual point of commencement of fuel injection from the time difference between the needle lift pulse and the TDC signal supplied by the engine speed sender. At the same time, the system compares the actual point of commencement of injection with the setpoint stored in the control unit and corrects any deviations from the setpoint.
Substitute function
If the needle lift sender fails, an emergency running program is started. In this program,
the commencement of fuel injection is controlled according to fixed setpoints
as defined in a map. The injection quantity reduced in addition.
The injector of the 3rd cylinder is equipped with a needle lift sender (G80) for registering
the point of commencement of injection.
The sender signals the actual opening time of the injector to the control unit. This
signal provides the control unit with feedback on whether the point of commencement
of fuel injection conforms to the map.
Function
Needle lift sender G80 is a solenoid and is supplied with a constant current by the control unit. This produces a magnetic field. A pressure pin inside the solenoid forms an extension to the end of the injector needle. The movement of the injector needle alters the magnetic field and causes distortion of the DC voltage applied to the solenoid.
The control unit calculates the actual point of commencement of fuel injection from the time difference between the needle lift pulse and the TDC signal supplied by the engine speed sender. At the same time, the system compares the actual point of commencement of injection with the setpoint stored in the control unit and corrects any deviations from the setpoint.
Substitute function
If the needle lift sender fails, an emergency running program is started. In this program,
the commencement of fuel injection is controlled according to fixed setpoints
as defined in a map. The injection quantity reduced in addition.
I think the sensor can't be replaced separately, you need a whole new injector. Anyone with access to ETKA confirm or deny?
funkmonkey66
Guest
Ah interesting, the 'substitute function' could be the last piece in the jigsaw of my running problems then. As I have posted before I've been having power/ boost problems, so far I have cleaned the egr and inlet and was planning on running some innotec through the turbo. But yesterday when I went for a drive I noticed that that turbo didn't seem to be cutting out as it was before but the car was still holding back and struggling to rev. Perhaps this is down to this default fuel map restricting the fuel to a 'safe' level. The overboost fault code has gone now anyway and I'm just left with this needle fault. A light a then end of the tunnel maybe, thanks for the input guys anymore is welcome.
funkmonkey66
Guest
Had a look this afternoon when i got home and i have a broken wire coming from the number 3 injector, that looks like me problem then! infact the wire is in a right mess so im not sure fixing the wire is an option, looks like a new injector is needed. Anyone know how much these are new? or have a spare one laying around doing nothing??? im going to start searching ebay now.
Isn't the wire part of the wiring harness? There should be a connector on the injector which the harness plugs in to.
funkmonkey66
Guest
No the wire comes out of the injector down to a plug about 4-5 inches down. The wire is broken between the injector and the plug. I'll see if I can sort out a pic. There's a couple of tdi's being broken on eBay, will ring tomorrow and see what engines they have. Drove the car again this evening and the turbo is spinning up nicely now so hopefully it's just this fueling issue hold the car back now.
Similar threads
