3rd injector needle lift sensor help

2 days ago my car suddenly started going into what felt like limp mode but would come back to normal intermittently with no consistency so I checked my fuel filter I drained a small amount of water then fuel went and put ps diesel 911 in it still assuming fuel gel or water (it was the coldest day we have had so far this year) still no help then the mil came on accompanied by a flashing glow plug light pulled codes with scanguage p1247 needle lift fault cleared it and went back to normal now power still comes and goes and I get intermittent or pending p1247 code I ohmed out the sensor and got 96 ohms checked for fuel restrictions which leads me to now be looking for a fuel pickup/sending unit either new or used... but after inspecting that I went back and ohmed it out again and got 3.47-9.58 K ohms and it fluctuated constantly it wouldn't settle out played with the wire from injector to connector with no change leading me to believe the wire is ok and the wires to the pcm got checked and are good.
So... i believe the spec for the sensor it 80-120 ohms if so what is causing it to change without being touched and also does it output a DC voltage or an ac sine wave to the pcm so I can monitor it with the engine running?

And lastly where is the best place to purchase a fuel sending unit?

Thanks in advance for any help!

You most likely have a frayed wire. I spliced a new connector on the engine wiring harness side. As far as I can tell, its a DC signal and it detects, quite well mind you, the movement of the needle as it disrupts the magnetic field in the coil.

Wow that is an excellent write up! Thanks for that! I did some more investigation and I checked the harness from the connector to the ecu and the wires seem ok even load test ok, but I am getting the injector sent out and repaired and will see if that fixes my issue I have parked it for now until I figure it out. Does that wire run through the orb of wires by that connector? Because mine is seized together

No, the third injector wire is separate from the Orb. Make sure it's the brown connector and not the black, I've seen them mixed up before.

1Z TDI Needle lift sensor

While I've been reading all the needle lift sensor posts I can find to help shed light on my P00542, "Needle lift sensor (G80), 30-10 open or short to plus - intermittent", one thing I haven't gotten clarity on is the wiring. I see references to a new style of wiring connector/harness being installed vs an old original one. On mine, I discovered a black wire under the jacketing - it is cut. It just ends there in the jacketing. This doesn't seem right. The manual doesn't show this and I have seen only one other post on this weirdness:
http://www.myturbodiesel.com/threads/p1246-trouble-code.4412/
The answer doesn't make a lot of sense to me.
Here's a pic of my wiring:


Is there a difference in years and or transmissions and G80 wiring?
What am I looking at? What should I do with the mystery black wire?

I remember the same, from when I was lengthening my harness, for the project car. I didn’t chase the black to see if it was unused at the ecu end.

-Todd

ToddA1, did it matter? Did the G80 work?

I wish I could answer that.... that would mean my project was finished. Maybe in a couple years, lol.

-Todd

The black wire most likely ends at a ground, its probably used in conjunction with the foil type insulation you see in the picture to help reduce electrical interference on those wires. The ecu only needs 2 wires the black one should have no effect on your concern, unless one of the other 2 wires are shorted to it

cumminsfromthecold said:

While I've been reading all the needle lift sensor posts I can find to help shed light on my P00542, "Needle lift sensor (G80), 30-10 open or short to plus - intermittent", one thing I haven't gotten clarity on is the wiring. I see references to a new style of wiring connector/harness being installed vs an old original one. On mine, I discovered a black wire under the jacketing - it is cut. It just ends there in the jacketing. This doesn't seem right. The manual doesn't show this and I have seen only one other post on this weirdness:
http://www.myturbodiesel.com/threads/p1246-trouble-code.4412/
The answer doesn't make a lot of sense to me.
Here's a pic of my wiring:

Is there a difference in years and or transmissions and G80 wiring?
What am I looking at? What should I do with the mystery black wire?

Click to expand...

I'm with Todd, my wagon conversion (98 MK3 ECU / wiring) has the same cut black wire, so ignore it.

There will be no difference in the Mk3 from 97-early 99 but with the B4 there have been differences mentioned in wiring for some things but how many variations there are is the question.

I have a 96 B4 harness that I compared to my 98 mk3 harness before install and there were maybe a handful of differences; catalyst sensors, 5th injector etc. For the most part my comparison found them pretty much identical.

Steve

I found my wiring notes from when I worked on my project, I can't find a completely black wire that goes to the ECU so I wouldn't worry about that.

I would bet that the black wire gets bundled with other ground wires somewhere further on in the harness although where that is I can't say.

Is that wire completely black or does it have a colored stripe on it?

Steve

Solid black, no tracer. I looked at the ecu plug the other day, while working on the project car. The black definitely didn’t to to a pin terminal.

As mentioned, it may gone to a ground wire cluster, but I wasn’t unwrapping the harness to find out.

-Todd

ToddA1 said:

Solid black, no tracer. I looked at the ecu plug the other day, while working on the project car. The black definitely didn’t to to a pin terminal.

As mentioned, it may gone to a ground wire cluster, but I wasn’t unwrapping the harness to find out.

-Todd

Click to expand...

Mine is still in the factory wrapping, the wire was cut and taped to the wire cover so almost no part of the black wire was showing.

I may put a meter on it tomorrow just to see if there's continuity to ground there.

I never noticed it before this post, which is odd since I unwrapped almost all of that entire harness when I stripped out the unnecessary stuff before installing it in the B3V.

Steve

I checked today, the black wire shows continuity to battery ground.

Steve

not to resurrect an old thread, but I was wondering what the dotted line around the two wires and going to the ground meant in the wiring diagram (bottom right), and as Cal stated in post #9, probably has something to do with reducing electrical interference.

Probably the foil shielding.

-Todd

Mine is identical -- with a "cut" black wire, and no foil insulation. I suspect this may have been something for the automatics, and not used in the manuals.

There were no automatic TDIs, in this generaion, at least in the US. You won’t see the foil, until you get under the insulation.

-Todd

Phi1osopher said:

Mine is identical -- with a "cut" black wire, and no foil insulation. I suspect this may have been something for the automatics, and not used in the manuals.

Click to expand...

The dashed line for AT is typically used for circuit paths. The dashed line for the G80 is different, the ground path you actually won't see because it goes back through the harness to the ECU and is likely combined with many other grounds.

ToddA1 said:

There were no automatic TDIs, in this generaion, at least in the US. You won’t see the foil, until you get under the insulation.

-Todd

Click to expand...

Correct for US, but there were some in Europe. Not sure how many but you could get it.

Steve