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catbed
02-27-2013, 04:09 PM
I'm trying to fix a torque intervention problem that I'm having whenever I plug the MAF in. The PO cut the MAF harness as it was a maf less tune, so I got a junkyard harness and I'm trying to splice it back in.

I got the wiring diagrams off of elsawin and got the 4 pins wired, but the black wire that is shielded with the green signal wire is just hanging right now. Elsawin says that it is a shield wire, and it terminates at the shielding for the green wire. Does this mean I just connect it to the shielding and that's it? Or should I ground it with the ground pin of the MAF? TIA

k0mpresd
02-27-2013, 05:24 PM
green is signal and plugs to maf and iirc the shielding is connected to ground back in the harness somewhere.

http://nefariousmotorsports.com/forum/index.php?topic=2839.0

http://i795.photobucket.com/albums/yy231/k0mpresd/maf_pins.png

catbed
02-27-2013, 05:40 PM
green is signal and plugs to maf and iirc the shielding is connected to ground back in the harness somewhere.

http://nefariousmotorsports.com/forum/index.php?topic=2839.0

http://i795.photobucket.com/albums/yy231/k0mpresd/maf_pins.png

Green is signal, yes. I am concerned about the black wire that shares the same shielded loom. The black wire meets the other shielded black wires in the ECU box, and then to the ECU. I am wondering if the black wire not being connected can send a wonky MAF signal. I can start and drive the car for about 10 mins before I get an EPC light, and a torque monitor 2 DTC.

k0mpresd
02-27-2013, 05:43 PM
so youre saying there are 5 wires going to your sensor?

there should be 4 wires.

bosch ecu/maf pin:

connects to 12v somewhere in car / 2 / +12v
27 / 3 / ground
53 / 4 / +5v
29 / 5 / signal

so maf pin 3 goes to ecu pin 27, ect.

catbed
02-27-2013, 06:14 PM
so youre saying there are 5 wires going to your sensor?

there should be 4 wires.

bosch ecu/maf pin:

connects to 12v somewhere in car / 2 / +12v
27 / 3 / ground
53 / 4 / +5v
29 / 5 / signal

so maf pin 3 goes to ecu pin 27, ect.

No, only 4 wires go to the sensor. I have connected the +12v, +5v, ground, and signal wires. The green signal wire is shielded/insulated along with another black wire. I am wondering where this black wire terminates at the connector. Do I just leave it unconnected or do I ground it to the shielding? I am not home right now, so I can't post the wiring diagram to help illustrate what I mean.

If I could see a pic of a stock MAF connector and where all the wires go that would be great.

Although I do remember now that the MAF harness got melted a bit at one point. I'll bust out the multi meter and report back.

Seerlah
02-27-2013, 07:13 PM
I cut my connector off too for my wire tuck and have the connector in front of me. That black wire just comes out the shielding with the green wire (pin 5) and just sits there. Connected to nothing.

catbed
02-27-2013, 07:19 PM
I cut my connector off too for my wire tuck and have the connector in front of me. That black wire just comes out the shielding with the green wire (pin 5) and just sits there. Connected to nothing.

Thank you very much. [wrench] I guess my next plan of attack is to look at that melted portion. [headbang] It didn't look like it melted all the way through but we shall see.

Seerlah
02-27-2013, 07:22 PM
Why not place the fully intact junk yard harness into your vehicle and keep your current one as a spare or parts one? More work yes, but just a better alternative IMO.

catbed
02-27-2013, 08:02 PM
Why not place the fully intact junk yard harness into your vehicle and keep your current one as a spare or parts one? More work yes, but just a better alternative IMO.

"New" AWM harnesses are upwards of $100, and I have already stripped and re-wrapped this harness multiple times, moved wires around, re-routed, deleted hardware, etc. It's just easier for me to figure out what's wrong, and I don't mind the troubleshooting.

Seerlah
02-27-2013, 08:07 PM
I paid like $125 for my current one, but it was in like perfect condition. Then I seen a "brand new" one from a Passat (AWM) being sold for the same price like 2 months ago. I wanted to pick it up so bad just on the premise of "because" [cool]. But I think another AZ member scooped it up (he sort of asked me not to bid, so I didn't. and there was only one bid at the end of the auction).