TBI Wiring Harness | Affordable Fuel Injection This is a basic TBI harness for all engines using ECM 1227747 and 1228746 type ECM-many others can be used. Basic connections are standard but it is easy to customize one for your needs. Typically, technical support is limited to the customer with only a harness purchase due to the complexity of variables we have no control over.Chevrolet · Toyota tbi harness | eBay Find great deals on eBay for tbi harness. Shop with confidence. Skip to main content. eBay Logo: 1 product rating - Painless Wiring 60101 GM TBI Fuel Injection Harness. $495. or Best Offer. Free Shipping. 25 new & refurbished from $439. Holley EFI 558-112 TERMINATOR EFI MAIN WIRING HARNESS-TBI,LSX, 58x. Brand New.