VW POLO: AUDI EPC LIGHT

AUDI HAS LOOMINITUS

Audi TT, A4 1.8T, A4 B5 1.8 Auto, 2.5 V6 Quattro B6, 1.6L A4 SE, 1.8L R4, Audi 8T0, Audi A6 C5,

Does your Audi occasionally have a hard time starting, yet finally starts just before you give up? So when it starts, the EPC and ESP lights are on, then the engine cuts out. You restart and she idles rough and the check engine light comes on? After a while the EPC and ESP light go out, thereafter the car drives normal until the next time this happens.

Or, as you are driving in manual mode, you noticed the ABS and ESP lights come on and suddenly your Audi's engine loses power and goes into limp mode. You switch off, then restart, it idles rough but won't rev over 1500 RPM and she sounds like a tractor. You switch off once again, restart and the tractor is gone. So you get the Audi home driving at a snails pace, the next morning you start her and it seems like there was never any problems because she now idles and drives normally.

Or you are VCDS savvy, encountered an EPC light problem, cleared the fault and the next day it come back on. Several days later the EPC light comes on again, stays on and refuses to switch off. Once again you do a scan and you get a ton of implausible and intermittent DTC errors.

Or your start the Audi, it idles for a few seconds then dies with the EPC light and ESP lights on. You clear the faults, lights go out. You drive the car for less than 3 km and it goes into limp mode. You disconnect the battery and reconnect and it seems fine thereafter. A few days later and the same thing occurs.

The Throttle body plug thats seem to haunt Audi owners.

What you have been experiencing is just a sampling of what the future holds. You Audi is suffering from "loominitus", its loom is having issues, better known to auto electricians and motor mechanics as wiring harness issues. The culprit in all the above case is the 6 pin plug interfacing with the throttle body. Of late, this throttle body plug has become quite trouble, you could almost call it common. Don't use contact spray on the plug. Ideally that portion of the loom needs to be replaced but since the female part of the plug is intermittent - hence faults come and go - it's worthwhile just replacing the plug and join the wires using ferrules and double crimp them. Cover the wires with shrink sleeving and avoid insulation tape because the engine heat will melt the PVC which will go sticky within days and its messy.

The troublesome Throttle body plug - connect thicker wires as per old plug.
Pin 1-blue/white stripe, Pin 2-purple/white stripe, Pin 3-white, Pin 4-blue/grey stripe, Pin 5-purple/black stripe, Pin 6-white/grey stripe

Throttle body replacement plug and colour coded wiring

I am so sorry to say, as the looms in the newer cars age, you should expect worse issues with the wiring harnesses. See the list of sub loom components for the VW Polo here. Pieces of the harness that makes-up the whole.

Anyway should you scan your ECU, you will most probably find the following faults and perhaps others not listed here. The image below points to the troublesome plug.

18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 35-10 - - - Intermittent
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
18084 - EPC Warning Lamp (K132) Circuit
P1676 - 35-00 - Electrical Malfunction
01176 - Key
65-10 - Unauthorized - Intermittent
01177 - Engine Control Unit
64-10 - Not Currently Testable - Intermittent
01119 - Gear Recognition Signal
35-10 - - - Intermittent
18264 - Throttle Potentiometer (G69): Error Message from ECU
P1856 - 35-10 - - - Intermittent
00258 - Mass Air Flow Sensor (G70)
P0102 - 002 - Signal too Low - Intermittent
18039 - Accelerator Position Sensor (G79)
P1631 - 35-00 - Signal too High
18042 - Accelerator Position Sensor 2 (G185)
P1634 - 35-00 - Signal too High
00768 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 - -
16685 - Cylinder 1: Misfire Detected
P0301 - 35-00 - -
16688 - Cylinder 4: Misfire Detected
P0304 - 35-00 - -
16690 - Cylinder 6: Misfire Detected
P0306 - 35-00 - -
16689 - Cylinder 5: Misfire Detected
P0305 - 35- 00 - -
17953 - Throttle Valve Controller
P1545 - 35-10 - Malfunction - Intermittent
17981 - Left Engine Mount Solenoid Valve (N144)
P1573 - 009 - Open Circuit
00473 - Control Module for Elect. Park/Hand Brake (J540)
008 - Implausible Signal - Intermittent
01494 - Bulb for Parking Lamps; Left (M1)
011 - Open Circuit
01504 - Bulb for License-Plate Light (X)
009 - Open or Short to Ground - Intermittent
02255 - Voltage Measuring Lead from Vbat
009 - Open or Short to Ground
16706 - Engine Speed Sensor (G28): No Signal
P0322 - 35-00 - -
00285 - ABS Wheel Speed Sensor; Front Right (G45)
008 - Implausible Signal - Intermittent
00283 - ABS Wheel Speed Sensor; Front Left (G47)
012 - Electrical Fault in Circuit - Intermittent
18057 - Powertrain Data Bus: Missing Message from ABS Controller
P1649 - 35-10 - - - Intermittent
16795 - Secondary Air Injection System: Incorrect Flow Detected
P0411 - 35-10 - - - Intermittent
17511 - Oxygen (Lambda) Sensor Heating; B1 S1: Performance too Low
P1103 - 35-10 - - - Intermittent
16497 - Intake Air Temp. Sensor (G42): Signal too High
P0113 - 35-10 - - - Intermittent
16955 - Brake Switch (F): Implausible Signal
P0571 - 35-00 - -