2000 b5 a4 1.8t atw wiring

**r77augh** · 03-05-2025 08:40 PM

Picked this car up from a junkyard complete (clean, low miles bad timing belt) except for the air filter top. Someone cut the harness at the air filter box only to get the air filter top, all the wiring was there and self explanatory just needed to be spliced back together except 3 wires (green/yellow stripe). the best of my knowledge these 3 wires in the harness go to the evap purge regulator thats attached to the top of the filter box, the MAF and the wastegate bypass regulator valve. Can anyone help me with the pinouts for these 3 sensors. i uploaded the pics of the sensors
1st- wire harness
2nd- wastegate bypass regulator valve (2 wire) white/yellow stripe and green/yellow stripe
3rd- evap purge regulator (2 wire) purple and green/yellow stripe
4th MAF (4 wire) yellow and green/yellow stripe and green/white stripe and little green wire but not sure where the little black wire goes to

**r77augh** · 03-06-2025 08:52 PM

no one? I did figure this part out but what are the numbers in the boxes after the sensors? wiring and my patience don't get along but I'm trying to get my car to run right, just need a little help

**walky_talky20** · 03-12-2025 07:35 PM

Firstly, the diagram you have shown there is an 97-99.5 AEB diagram (Drive by Throttle Cable). It is wildly different from the ATW car you have. You've probably noticed this already, but I wanted to point it out.

Info Below Applicable to Drive By Wire cars (ATW and AWM):

The Green/Yellow wires are the 12v power to many of the various engine sensors and actuators. The Green/Yellow stuff is lit up from Fuse #34, which is one of the 3 fuses that are energized by the Fuel Pump Relay:

Fuel Pump Relay Outputs:
Fuse 28 - Fuel Pump itself (GREEN/YELLOW)
Fuse 32 - Fuel Injectors (BLACK/BLUE)
Fuse 34 - MAF/N75(Boost Solenoid)/N249(DV Solenoid)/N112 (SAI Solenoid)/N80(Purge Solenoid)/O2 Sensor Heaters/Etc. (GREEN/YELLOW)

"The numbers in the boxes after the sensors":
- I'm assuming you mean the "65" and "60" near the bottom of the diagram coming from the N75 and G70(MAF) respectively.
- These are the horizontal reference numbers (column numbers) across the bottom of the diagram itself. In your photo, you can see the numbers across the bottom of the diagram go from 10 up through 21.
- The number "65" in a rectangle box means that particular wire connects to something on column 65. So you would flip a few pages to the right to Column 65 where you will find a matching box that says "18" (linking back to the page you've shown - Column 18). This simply avoids drawing a horizontal connecting wire across 8 pages of the diagram or whatever.

That said, this is the wrong diagram for your car. I have one that is a lot more accurate, in color, and an easier to read format if you want. Please PM me your email address and I can send it to you. It's an AWM Engine diagram, but it is the same except for the primary o2 sensor and the VVT solenoid.

**r77augh** · 03-15-2025 06:37 PM

Originally Posted by walky_talky20

Firstly, the diagram you have shown there is an 97-99.5 AEB diagram (Drive by Throttle Cable). It is wildly different from the ATW car you have. You've probably noticed this already, but I wanted to point it out.

Info Below Applicable to Drive By Wire cars (ATW and AWM):

The Green/Yellow wires are the 12v power to many of the various engine sensors and actuators. The Green/Yellow stuff is lit up from Fuse #34, which is one of the 3 fuses that are energized by the Fuel Pump Relay:

Fuel Pump Relay Outputs:
Fuse 28 - Fuel Pump itself (GREEN/YELLOW)
Fuse 32 - Fuel Injectors (BLACK/BLUE)
Fuse 34 - MAF/N75(Boost Solenoid)/N249(DV Solenoid)/N112 (SAI Solenoid)/N80(Purge Solenoid)/O2 Sensor Heaters/Etc. (GREEN/YELLOW)

"The numbers in the boxes after the sensors":
- I'm assuming you mean the "65" and "60" near the bottom of the diagram coming from the N75 and G70(MAF) respectively.
- These are the horizontal reference numbers (column numbers) across the bottom of the diagram itself. In your photo, you can see the numbers across the bottom of the diagram go from 10 up through 21.
- The number "65" in a rectangle box means that particular wire connects to something on column 65. So you would flip a few pages to the right to Column 65 where you will find a matching box that says "18" (linking back to the page you've shown - Column 18). This simply avoids drawing a horizontal connecting wire across 8 pages of the diagram or whatever.

That said, this is the wrong diagram for your car. I have one that is a lot more accurate, in color, and an easier to read format if you want. Please PM me your email address and I can send it to you. It's an AWM Engine diagram, but it is the same except for the primary o2 sensor and the VVT solenoid.

thanks for the info, i messaged you my email