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Performance Engineered in the USA: Proven Gains for Street and Track Builds
The Kooks EX685-Z O2 sensor extension harness solves the common wiring reach issue when installing long-tube headers on 2014 and 2019 Corvette C7 models (Stingray, Grand Sport, Z06), providing a plug-and-play solution that repositions both front and rear oxygen sensors for accurate air-fuel monitoring and ECU calibration without triggering check engine lights or lean/rich codes.
Built from high-temperature shielded wiring with OEM-style weatherproof connectors rated over 1,200°F, this harness maintains perfect signal integrity under extreme exhaust heat and vibration from high-RPM or track use. The kit includes both driver and passenger side extensions with correct length for Kooks header installations and no cutting or excess slack that could cause chafing.
For C7 Corvette owners upgrading to aftermarket headers, the EX685-Z harness is the essential wiring solution for seamless installation and flawless engine management.
Key Features
- Driver & passenger side front/rear O2 extensions
- OEM-style weatherproof connectors
- High-temp shielded wiring rated over 1,200°F
- Plug-and-play and no cutting or splicing
- Prevents CEL from O2 sensor relocation
- Direct fit for Kooks C7 header kits
Product Notes
- Fits all 2014 and 2019 Corvette C7 models
- Compatible with LT1 and LT4 engines
- Required when installing Kooks long-tube headers
California Proposition 65: Contains chemicals known to the State of California to cause cancer or reproductive harm.
Warranty: Limited lifetime against manufacturing defects to original purchaser.
Installation Notes
- Unplug factory O2 sensors
- Route extensions along factory harness path
- Plug into original harness and relocated sensors
- Secure with zip ties and avoid exhaust contact
This Part Fits
| Year | Make | Model | Engine |
|---|---|---|---|
| 2014 and 2019 | Chevrolet | Corvette C7 | LT1 6.2L / LT4 6.2L Supercharged |
Note: Universal fit for C7 with Kooks long-tube headers. All trims.
What's Included in the Purchase
- (2) Front O2 Sensor Extension Harnesses
- (2) Rear O2 Sensor Extension Harnesses
- Part Number: Kooks EX685-Z
Why Choose Kooks?
- Over 60 years of championship-winning exhaust engineering
- Precision wiring components tested in 1,000+ HP builds
- Limited lifetime warranty and expert support
Frequently Asked Questions
-
Q: Does this include front and rear?
A: Yes and 4 total extensions (both banks) -
Q: Will it work with non-Kooks headers?
A: Yes, fits any C7 header requiring O2 relocation -
Q: Prevents CEL?
A: Yes, maintains factory sensor positioning logic -
Do Kooks headers require a tune after installation?
Yes. A professional tune is strongly recommended after installing long tube headers. The significant improvement in exhaust flow changes air fuel ratios and requires ECM recalibration to achieve optimal power output and safe operation. -
Will these headers void my factory powertrain warranty?
Under the Magnuson-Moss Warranty Act, a manufacturer cannot void your vehicle warranty simply because you installed an aftermarket part unless they prove the component directly caused the failure. Consult your dealer for specifics on your situation. -
Q: Do these Kooks headers require a tune after installation?
A: Yes. A professional tune is strongly recommended after installing long tube headers. The significant improvement in exhaust flow changes air fuel ratios and requires ECM recalibration to achieve optimal power output and safe operation. -
Q: Will Kooks headers void my factory powertrain warranty?
A: Under the Magnuson-Moss Warranty Act, a manufacturer cannot void your vehicle warranty simply because you installed an aftermarket part unless they prove the component directly caused the failure in question. Consult your dealer for specifics. -
Q: What warranty does Kooks provide?
A: Kooks products are backed by a limited lifetime warranty to the original purchaser against defects in materials and workmanship. Racing and competition use applications may have specific warranty exclusions. Contact Kooks Performance directly for warranty details.
Shipping & Handling
- Method: UPS or Fed Ex Ground.
- Availability: Typically ships same day or next if in stock.
- Packaging: Anti-static bag in protective box.
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