Welcome to EFI Connection

EFI Connection offers replacement GM harness connector pigtails, benchtop programming harnesses for many GM engine and transmission controllers, and other fuel injection related parts. Please contact us with any questions you may have about our work or to discuss your custom project.

Unassembled Connector Pigtails

We assemble all of the connector pigtails we offer, so we do stock all connectors, terminals, cable seals, etc. While we are willing to offer these connector pigtails unassembled, it is very important that you understand there is a specific crimp tool or die for each terminal. A generic crimp tool will not provide a quality crimp. We do offer several crimp tools for these terminals. Buyers of unassembled pigtails will assume their own risk in crimping terminals to their wire harness. Please contact us to discuss ordering unassembled connector pigtails. We will provide a quote and availability.

International Orders

We frequently ship internationally! At this time our paypal shopping cart does not allow for international shipping rates, so if we can not get your package to your address with the shipping calculated by paypal's shopping cart, we will send an additional paypal payment request for the remaining shipping costs. While most items are shipped First Class International Mail, we prefer to ship internationally using USPS Express Mail International. This service provides quick delivery and tracking information, First Class International Mail does not.

Large Quantities

Do you have a need for a large quantity of something on our website or some other GM related connector pigtail or extension harness? Please contact us to discuss such an order. We will provide a quote and estimated time to build.

Payment and Shipping

Custom wiring harnesses will be invoiced by email. All other items on this website may be purchased through the PayPal shopping cart by clicking the "Add to Cart" buttons. In most cases, all items are shipped the following business day using First Class USPS mail. When items are shipped First Class mail, you will receive a delivery confirmation number by email. USPS calls this a tracking number, but it is actually only a delivery confirmation number and will only show online status when your package is delivered.

Frequently Asked Questions

I'm looking for a replacement connector pigtail for a [non-GM vehicle]...
We do not offer replacement connectors for Ford, Lexus, Jaguar, Chrysler, Honda, or any other non-GM vehicle. Please see your local dealership or your local auto wrecking yard for non-GM connectors.

I'm looking for a GM replacement connector pigtail that I do not see on this website...
We stock many different replacement connectors for GM applications. Please contact us with any special requests.