How to repair/replace wire - Loud rattle/shaking + chewed wire - 2017 Prius C

There are very few repair jobs that are easier than this... Almost anyone who has basic wiring skills could do it in 5 minutes.

 

The Electrical Wiring Diagram (more info) shows that’s connector C1, for Fuel Injector Assembly No. 1. The engine is rattling and shaking because the cylinder isn’t getting fuel.

If it were my car, I’d buy this set of fuel injectors and their connectors for sale on eBay for $65:

12-19 Toyota Prius C Fuel Injector Injectors Set 1.5L L4 OEM 13 14 15 16 17 18 | eBay

(I have no connection with the seller.)

That would get you a replacement connector—the black one with green and gray wires, second from the left in the seller’s first picture—with the correct terminals and seals already installed. The price isn’t much more than the cost of the two repair wires (pigtails) you’d have to buy instead from a Toyota dealer, but it would avoid the need to extract the old terminals and install the new pigtails into the old connector housing, which can be tricky if you’ve never done it before.

Instead, you could cut off only the damaged sections of the green and gray wires going to the old connector, leaving as much of the existing wire as possible, and then splice them to the short green and gray wires from the new connector, as described in Toyota’s Wire Harness Repair Manual (PDF), pages B-30 (46) through B-35 (51), step 3, items 1 through 6, and in an old Toyota video (from 16:26 to 17:37).

You’d need parallel splices (sleeves) (probably the blue size, but maybe the yellow size, depending on how large the wires are), a suitable crimping tool, and self-fusing silicone tape.

If you decide to do the work yourself, see the precautions in the Owner’s Manual (PDF), pages 414–415, and if you’re not confident in the result, consider taking the car to a shop to have it checked and redone if necessary.