1.8T MK4 Wire Tucked Complete Engine Harness Wideband ECU's only AWP, AWW, BEA, BAM - V1
QUICK DISCONNECT VERSIONS HAVE BEEN DISCONTINUED, V2 RELEASED WITHOUT QUICK DISCONNECT, YOU CAN PURCHASE HERE.
Introducing the Carrot Top Tuning 1.8T VW MK4 Engine Tucked Harness - Now available in three convenient stages for your customization needs:
Stage 1: Our Stage 1 kit comprises the essential ECU 40 pin engine loom with a quick-connect feature, ensuring seamless installation and removal. Can be utilized with the OE 81 pin side harness.
Stage 2: Elevate your wiring setup with our Stage 2 package, which includes the 40 Pin main loom and the 81 pin connector. This connector houses critical components such as the O2 sensor, Main ECU Relay, Fuel Pump Relay, Starter Signal, Reverse Lights, Mass Airflow Sensor, and Coil power input, offering a comprehensive solution for your engine harness needs.
Stage 3 (In Development): Stage 3, currently in development, will take your engine bay aesthetics to the next level by enabling the relocation of the body harness for a cleaner appearance.
Our design philosophy prioritizes versatility, catering to both dedicated track cars and daily drivers. Crafted with PTFE Teflon high-temperature resistant wiring, our harness can withstand extreme temperature fluctuations, ranging from -90 °C to 260 °C. Each connector is meticulously labeled for easy identification and component removal without disconnecting the main loom from the engine. The inclusion of a milspec quick connect on the frame rail simplifies the installation process.
Furthermore, our harness features an integrated Fuel Pump relay for additional AUX Fuel Pump applications, ideal for fuel-hungry setups or surge tanks within the engine bay. You'll also find a removable partial coil expansion harness, injector connectors, N75 (for manual boost controller applications), and MAF (for maffless setups) to streamline your engine bay by eliminating unnecessary connections. Additionally, we provide a secondary wideband hookup at the OE location beneath the car. The top connector conveniently links to an AFR gauge, eliminating the need for extra wiring through the chassis.
Connector Abbreviation Overview:
40 Pin ECU Connector:
Ignition Coils (1-4)
INJ1, INJ2, INJ3, INJ4 (Fuel Injectors)
VSS (Vehicle Speed Sensor)
N75 (Boost Control Solenoid - Resistor required if removed)
IAT (Intake Air Temp Sensor)
BT (Throttle Body)
OIL (Oil Pressure Switch)
CRANK (Crankshaft Position Sensor)
MAP (Boost Pressure Sensor - Choose stock location or under the intake manifold, one must be used)
ECT (Coolant Temp Sensor)
KS2 (Knock Sensor Cyl 3-4)
KS1 (Knock Sensor Cyl 1-2)
CAM (Camshaft Position Sensor)
COILS (Ignition Coil Expansion Harness)
N249 (Resistors Included)
COIL 12V (Ignition Coil Power output)
CHASSIS (Multi-Pin Connector Near the Battery in factory location)
GROUND (Chassis Ground)
81 Pin ECU Connector:
N112, N80 (Resistors Included)
ECU (Main ECU Relay)
FP AUX (Additional Fuel Pump Relay)
Wideband (Main O2 Sensor - 6 Pin connector, suitable for AFR gauge hookup, LSU 4.9 O2 Sensor Compatible Gauges)
FP 12V IN (12V+ Ignition Source for powering the AUX fuel pump - Optional, run the expansion harness down to the terminals inside the car, connects to 75xx Yellow Terminal or the Battery direct)
FP 12V OUT (12+ Ignition Output for the AUX Fuel pump, connects directly to the positive terminal on the AUX pump - Optional)
GROUND (Chassis Ground)
ST (Starter Signal)
REV (Reverse Lights)
MAF (Mass Airflow Sensor)
COIL 12V (Ignition Coil Power input)
O2 Sensor - Main ECU O2 sensor OE sensor should be used.
O2 AUX - Secondary O2 sensor for an AFR gauge (optional)
***PLEASE NOTE: THIS HARNESS IS FOR WIDEBAND ECU'S ONLY, IF YOU HAVE AN AWD, AMU, APX ENGINE CODE YOU WILL NEED AN AWP, OR AWW ECU TO FUNCTION CORRECTLY.
In some instances with some ECU's you may observe intermittent open circuit ghost codes for ignition coils, you must have your tuner remove these codes to clear the CEL. The codes do not affect performance of the vehicle, or the harness.
P1355 - 17763 - Cylinder 1 Ignition Circuit (Open Circuit) Intermittent
P1358 - 17766 - Cylinder 2 Ignition Circuit (Open Circuit) Intermittent
P3631 - 17769 - Cylinder 3 Ignition Circuit (Open Circuit) Intermittent
P1364 - 17772 - Cylinder 4 Ignition Circuit (Open Circuit) Intermittent
QUICK DISCONNECT VERSIONS HAVE BEEN DISCONTINUED, V2 RELEASED WITHOUT QUICK DISCONNECT, YOU CAN PURCHASE HERE.
Introducing the Carrot Top Tuning 1.8T VW MK4 Engine Tucked Harness - Now available in three convenient stages for your customization needs:
Stage 1: Our Stage 1 kit comprises the essential ECU 40 pin engine loom with a quick-connect feature, ensuring seamless installation and removal. Can be utilized with the OE 81 pin side harness.
Stage 2: Elevate your wiring setup with our Stage 2 package, which includes the 40 Pin main loom and the 81 pin connector. This connector houses critical components such as the O2 sensor, Main ECU Relay, Fuel Pump Relay, Starter Signal, Reverse Lights, Mass Airflow Sensor, and Coil power input, offering a comprehensive solution for your engine harness needs.
Stage 3 (In Development): Stage 3, currently in development, will take your engine bay aesthetics to the next level by enabling the relocation of the body harness for a cleaner appearance.
Our design philosophy prioritizes versatility, catering to both dedicated track cars and daily drivers. Crafted with PTFE Teflon high-temperature resistant wiring, our harness can withstand extreme temperature fluctuations, ranging from -90 °C to 260 °C. Each connector is meticulously labeled for easy identification and component removal without disconnecting the main loom from the engine. The inclusion of a milspec quick connect on the frame rail simplifies the installation process.
Furthermore, our harness features an integrated Fuel Pump relay for additional AUX Fuel Pump applications, ideal for fuel-hungry setups or surge tanks within the engine bay. You'll also find a removable partial coil expansion harness, injector connectors, N75 (for manual boost controller applications), and MAF (for maffless setups) to streamline your engine bay by eliminating unnecessary connections. Additionally, we provide a secondary wideband hookup at the OE location beneath the car. The top connector conveniently links to an AFR gauge, eliminating the need for extra wiring through the chassis.
Connector Abbreviation Overview:
40 Pin ECU Connector:
Ignition Coils (1-4)
INJ1, INJ2, INJ3, INJ4 (Fuel Injectors)
VSS (Vehicle Speed Sensor)
N75 (Boost Control Solenoid - Resistor required if removed)
IAT (Intake Air Temp Sensor)
BT (Throttle Body)
OIL (Oil Pressure Switch)
CRANK (Crankshaft Position Sensor)
MAP (Boost Pressure Sensor - Choose stock location or under the intake manifold, one must be used)
ECT (Coolant Temp Sensor)
KS2 (Knock Sensor Cyl 3-4)
KS1 (Knock Sensor Cyl 1-2)
CAM (Camshaft Position Sensor)
COILS (Ignition Coil Expansion Harness)
N249 (Resistors Included)
COIL 12V (Ignition Coil Power output)
CHASSIS (Multi-Pin Connector Near the Battery in factory location)
GROUND (Chassis Ground)
81 Pin ECU Connector:
N112, N80 (Resistors Included)
ECU (Main ECU Relay)
FP AUX (Additional Fuel Pump Relay)
Wideband (Main O2 Sensor - 6 Pin connector, suitable for AFR gauge hookup, LSU 4.9 O2 Sensor Compatible Gauges)
FP 12V IN (12V+ Ignition Source for powering the AUX fuel pump - Optional, run the expansion harness down to the terminals inside the car, connects to 75xx Yellow Terminal or the Battery direct)
FP 12V OUT (12+ Ignition Output for the AUX Fuel pump, connects directly to the positive terminal on the AUX pump - Optional)
GROUND (Chassis Ground)
ST (Starter Signal)
REV (Reverse Lights)
MAF (Mass Airflow Sensor)
COIL 12V (Ignition Coil Power input)
O2 Sensor - Main ECU O2 sensor OE sensor should be used.
O2 AUX - Secondary O2 sensor for an AFR gauge (optional)
***PLEASE NOTE: THIS HARNESS IS FOR WIDEBAND ECU'S ONLY, IF YOU HAVE AN AWD, AMU, APX ENGINE CODE YOU WILL NEED AN AWP, OR AWW ECU TO FUNCTION CORRECTLY.
In some instances with some ECU's you may observe intermittent open circuit ghost codes for ignition coils, you must have your tuner remove these codes to clear the CEL. The codes do not affect performance of the vehicle, or the harness.
P1355 - 17763 - Cylinder 1 Ignition Circuit (Open Circuit) Intermittent
P1358 - 17766 - Cylinder 2 Ignition Circuit (Open Circuit) Intermittent
P3631 - 17769 - Cylinder 3 Ignition Circuit (Open Circuit) Intermittent
P1364 - 17772 - Cylinder 4 Ignition Circuit (Open Circuit) Intermittent
- Fitment verified for YOUR exact year/model/trim
- Not sure? Call +1 772-277-2495 for a real specialist to help you order
- Got install questions? Text a tech who's actually installed this part before, even after it arrives
FREE Shipping
Select your exact model and see if this part fits
1.8T MK4 Wire Tucked Complete Engine Harness Wideband ECU's only AWP, AWW, BEA, BAM - V1 - Stage 1 - Engine Loom Only 40 Pin is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Wrong fit or arrives damaged? Free replacement or refund
30,000+ Happy Customers
30-Day Returns
One Year Warranty
Details
Details
QUICK DISCONNECT VERSIONS HAVE BEEN DISCONTINUED, V2 RELEASED WITHOUT QUICK DISCONNECT, YOU CAN PURCHASE HERE.
Introducing the Carrot Top Tuning 1.8T VW MK4 Engine Tucked Harness - Now available in three convenient stages for your customization needs:
Stage 1: Our Stage 1 kit comprises the essential ECU 40 pin engine loom with a quick-connect feature, ensuring seamless installation and removal. Can be utilized with the OE 81 pin side harness.
Stage 2: Elevate your wiring setup with our Stage 2 package, which includes the 40 Pin main loom and the 81 pin connector. This connector houses critical components such as the O2 sensor, Main ECU Relay, Fuel Pump Relay, Starter Signal, Reverse Lights, Mass Airflow Sensor, and Coil power input, offering a comprehensive solution for your engine harness needs.
Stage 3 (In Development): Stage 3, currently in development, will take your engine bay aesthetics to the next level by enabling the relocation of the body harness for a cleaner appearance.
Our design philosophy prioritizes versatility, catering to both dedicated track cars and daily drivers. Crafted with PTFE Teflon high-temperature resistant wiring, our harness can withstand extreme temperature fluctuations, ranging from -90 °C to 260 °C. Each connector is meticulously labeled for easy identification and component removal without disconnecting the main loom from the engine. The inclusion of a milspec quick connect on the frame rail simplifies the installation process.
Furthermore, our harness features an integrated Fuel Pump relay for additional AUX Fuel Pump applications, ideal for fuel-hungry setups or surge tanks within the engine bay. You'll also find a removable partial coil expansion harness, injector connectors, N75 (for manual boost controller applications), and MAF (for maffless setups) to streamline your engine bay by eliminating unnecessary connections. Additionally, we provide a secondary wideband hookup at the OE location beneath the car. The top connector conveniently links to an AFR gauge, eliminating the need for extra wiring through the chassis.
Connector Abbreviation Overview:
40 Pin ECU Connector:
Ignition Coils (1-4)
INJ1, INJ2, INJ3, INJ4 (Fuel Injectors)
VSS (Vehicle Speed Sensor)
N75 (Boost Control Solenoid - Resistor required if removed)
IAT (Intake Air Temp Sensor)
BT (Throttle Body)
OIL (Oil Pressure Switch)
CRANK (Crankshaft Position Sensor)
MAP (Boost Pressure Sensor - Choose stock location or under the intake manifold, one must be used)
ECT (Coolant Temp Sensor)
KS2 (Knock Sensor Cyl 3-4)
KS1 (Knock Sensor Cyl 1-2)
CAM (Camshaft Position Sensor)
COILS (Ignition Coil Expansion Harness)
N249 (Resistors Included)
COIL 12V (Ignition Coil Power output)
CHASSIS (Multi-Pin Connector Near the Battery in factory location)
GROUND (Chassis Ground)
81 Pin ECU Connector:
N112, N80 (Resistors Included)
ECU (Main ECU Relay)
FP AUX (Additional Fuel Pump Relay)
Wideband (Main O2 Sensor - 6 Pin connector, suitable for AFR gauge hookup, LSU 4.9 O2 Sensor Compatible Gauges)
FP 12V IN (12V+ Ignition Source for powering the AUX fuel pump - Optional, run the expansion harness down to the terminals inside the car, connects to 75xx Yellow Terminal or the Battery direct)
FP 12V OUT (12+ Ignition Output for the AUX Fuel pump, connects directly to the positive terminal on the AUX pump - Optional)
GROUND (Chassis Ground)
ST (Starter Signal)
REV (Reverse Lights)
MAF (Mass Airflow Sensor)
COIL 12V (Ignition Coil Power input)
O2 Sensor - Main ECU O2 sensor OE sensor should be used.
O2 AUX - Secondary O2 sensor for an AFR gauge (optional)
***PLEASE NOTE: THIS HARNESS IS FOR WIDEBAND ECU'S ONLY, IF YOU HAVE AN AWD, AMU, APX ENGINE CODE YOU WILL NEED AN AWP, OR AWW ECU TO FUNCTION CORRECTLY.
In some instances with some ECU's you may observe intermittent open circuit ghost codes for ignition coils, you must have your tuner remove these codes to clear the CEL. The codes do not affect performance of the vehicle, or the harness.
P1355 - 17763 - Cylinder 1 Ignition Circuit (Open Circuit) Intermittent
P1358 - 17766 - Cylinder 2 Ignition Circuit (Open Circuit) Intermittent
P3631 - 17769 - Cylinder 3 Ignition Circuit (Open Circuit) Intermittent
P1364 - 17772 - Cylinder 4 Ignition Circuit (Open Circuit) Intermittent
Fitment
Fitment
Our Guarantee
Our Guarantee
Warranty Assurance:
At K2 Industries, your satisfaction is our priority, and we stand behind the quality of our products. Here's a brief overview of our warranty:
Defect Coverage:
If you find a defect after receiving your order, get in touch with us. We're committed to resolving the issue, whether it involves a replacement, repair, or refund.
Installation Note:
Please inspect your purchase before installation. Unfortunately, damages post-installation are not covered, so ensure everything looks good beforehand.
Claims Made Simple:
Need to make a claim? Reach out to us at support@k2-industries.com. We're here to assist you. Just keep your original packaging and documentation handy.
Your Satisfaction Matters:
Your trust in K2 Industries is appreciated. We're dedicated to ensuring your satisfaction with our quality automotive parts.
Shipping & Returns
Shipping & Returns
Shipping Information:
At K2 Industries, we strive to provide a seamless and efficient shopping experience for automotive enthusiasts like you. Our commitment is to deliver high-quality parts to your doorstep with the utmost care.
Fast and Reliable Shipping:
Many of our products are stocked in our local warehouse, ensuring swift processing and delivery. Orders placed for these items typically ship within 2-5 business days, allowing you to get your parts in no time.
Extended Selection, Global Reach:
To offer you a broader range of automotive parts, some items are sourced from trusted suppliers around the world. While these products might have a slightly longer processing time, we assure you that the wait is worth it for the exceptional quality and value they bring.
Shipping Transparency:
For products shipped internationally, we provide estimated delivery times on the product page. Rest assured, we are continually working to optimize our supply chain and minimize any potential delays.
Combined Shipments:
To streamline your shopping experience, if your order includes items from both our local warehouse and international suppliers, they may be shipped separately. You will receive separate tracking information for each shipment.
Questions or Concerns?
If you have any questions about shipping or would like assistance tracking your order, our dedicated customer support team is here to help. Feel free to reach out to us at support@k2-industries.com.
You can also track your order here
Thank you for choosing K2 Industries for your automotive needs. We appreciate your trust in us.
FAQs
How do I confirm this part fits my vehicle?
Use the vehicle selector at the top of this page to verify fitment. If anything's unclear, send us your year/model/trim (or VIN) via live chat or email support@k2-industries.com — we'll confirm fitment for free, before you commit.
How long until I get my order?
In-stock items typically process in 3-5 business days, then ship — most domestic orders arrive within 3-7 business days after that. Larger freight items take 3-10 days in transit. Some items are made-to-order (carbon fiber, aero kits) and require 10-25 business days of production before shipping — these are marked on the product page.
What if it arrives damaged?
Inspect your shipment when it arrives, take photos of any damage to the box and part, and reach out via live chat or support@k2-industries.com. For freight deliveries, note visible damage on the paperwork before signing. We handle the carrier claim and get you a replacement.
What if I want to return it?
You have 30 days from delivery. As long as the part is uninstalled and in original condition, you can choose between an exchange, store credit (no fees, never expires — our most popular option), or a refund. Drop us a message and we'll walk you through the easiest path.
Can I install this myself, or do I need a shop?
Depends on the part. Some are straightforward DIY, others are body shop or specialist work. Each product page indicates the recommended install path. If you're unsure, message us with your build details and we'll give you a real assessment.
What's the fastest way to reach you?
Live chat and email — typical response time is a few business hours, and you can reach out anytime. Chat with us on the site or email support@k2-industries.com. We resolve issues directly far faster than going through your bank or card processor.
The K2 Difference
- • Built by enthusiasts who've made every fitment mistake you're afraid of. Now we verify parts for 30,000+ builds a year with zero wrong-part claims.
- • Real specialists answer your questions in minutes, not chatbots reading scripts. We've built the same cars you're building.
- • Freight damage, wrong parts, installation question, we handle it so you don't deal with suppliers or shipping companies.
Built By Someone Who's Been There
Max, the Owner, started in his garage making E36 M3 tail lights in his own oven.
- • Started modifying cars before he could legally drive them
- • Spent years hunting down parts that actually fit and don't suck
- • Made the same fitment mistakes you're afraid of
What You Get With Every Order
What Sets K2 Industries Apart?
Perfect fit guaranteedFrequently Asked Questions
How do I know this will actually fit my car?
How do I know this will actually fit my car?
Every part listing shows compatible years, models, and trims. But here's the thing—trim packages and factory options can be confusing. If you're not 100% certain, text us at 772-277-2495 with your VIN or photos of your car. We'll verify fitment before you order so you're not stuck with an $800 part that doesn't fit. We've done this for 30,000+ builds. We've seen every weird trim combo and factory option. Takes us 2 minutes to verify, saves you weeks of headaches.
What if the part arrives damaged or is the wrong item?
What if the part arrives damaged or is the wrong item?
We handle it. You don't fight with freight companies or file claims. Text us photos within 48 hours of delivery. If it's damaged or wrong, we ship a replacement immediately. You're not waiting 6 weeks for a freight claim to process. We eat the cost, not you. This is why we package everything like it's going to war. But if something slips through, we fix it ASAP. No forms, no back-and-forth, no "file a claim and wait." Just text us and we handle it.
Can I install this myself or do I need a shop?
Can I install this myself or do I need a shop?
Depends on the part. Emblems, front lips, some spoilers, bolt-on, DIY-friendly, you can do it in your driveway with basic tools. Full bumpers, hoods, wide-body kits, possible for experienced DIYers but most people take them to a shop for paint and install. Check the product description for installation difficulty. If you're unsure, text us. We'll be honest about whether you can handle it or if you should take it to a pro. We'd rather you know upfront than get frustrated halfway through.
What's your return policy if it doesn't fit or I don't like it?
What's your return policy if it doesn't fit or I don't like it?
30 days, unused parts in original packaging. You pay return shipping unless we sent the wrong part or it arrived defective. Once you install it, modify it, paint it, or mount it, we can't take it back. That's why we push so hard on verifying fitment BEFORE you order. We don't want you stuck with something you can't use. Text us before ordering if you're unsure. We'll confirm fitment so you never have to worry about returns.
Do you offer financing?
Do you offer financing?
Yes. Affirm and Shop Pay available at checkout for orders over $50. Split payments over 3-12 months depending on order size. No hard credit check to see your options. Most people use this for big-ticket items like body kits, suspension setups, or wheel/tire packages. Rates vary based on credit. You see the monthly payment before you commit. Makes it easier to build now instead of waiting months to save up.
What if I have questions after I receive the part?
What if I have questions after I receive the part?
Text 772-277-2495. We don't disappear after you buy. Fitment questions, installation issues, "does this bolt go here" questions... we'll walk you through it. We've installed these parts ourselves or helped hundreds of people install them. You're not getting transferred to a call center in the Philippines. You're texting someone who's actually installed your part before. If we can't help remotely, we'll recommend a local shop that knows these parts.
Why should I buy from K2 instead of eBay/Amazon/other sites?
Why should I buy from K2 instead of eBay/Amazon/other sites?
eBay and Amazon sellers don't answer fitment questions. They don't verify your VIN before shipping. They don't handle freight damage claims for you. If something goes wrong, you're filing disputes and waiting weeks. We're builders selling to builders. We verify fitment before you order. We handle damage claims same-day. We answer texts in minutes. We're not the cheapest, but you're not gambling $800 on whether a part fits. You're paying for support, verification, and someone who cares if your build goes sideways.
What does your warranty cover?
What does your warranty cover?
1 year against manufacturing defects: cracking, warping, paint peeling, hardware failure, fitment issues caused by the part being made wrong. Does NOT cover installation damage (you cracked it bolting it on), road damage (curb rash, rock chips), or normal wear. If it breaks because we made it wrong, we replace it free. If it breaks because you hit a parking block, that's on you. We're fair about it. Send photos and we'll tell you honestly if it's covered.
Shipping
Do you ship overseas?
Do you ship overseas?
Yes, we ship all over the world. Shipping costs will apply, and will be added at checkout. We run discounts and promotions all year, so stay tuned for exclusive deals.
How much does shipping cost and when will I see the total?
How much does shipping cost and when will I see the total?
Depending on where you're located, small parts can ship free. Large parts like bumpers, hoods, and body kits require freight shipping. Uou'll see the exact cost at checkout before you pay. Freight usually runs $150-$300 depending on size and your location. We know it's expensive. We negotiate the best rates we can. If you're ordering multiple large parts, text us. We can sometimes combine shipping and save you money. We're not hiding fees in the final step. What you see at checkout is what you pay.
How long will it take to receive my order?
How long will it take to receive my order?
It depends on where you are. Orders processed here will take 5-7 business days to arrive. Overseas deliveries can take anywhere from 7-16 days. Delivery details will be provided in your confirmation email.
