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7.3L UVC Harness Retainer Clips

Glossary

This article is to illustrate the use of under valve cover (UVC) harness Retaining clips (pictured on the right) in a 7.3L Power Stroke Engine. A service kit that has been made available to service UVC harness connectors that have weakened and worked loose causing open injector circuits. Typical complaints are engine misfire, rough idle, lack of power, check engine light on and in some cases a no start condition. When one or more of these UVC connectors loosens and becomes partially disconnected the result is one or more injector circuits becomes electrically open. If a connector becomes loose enough it can disable a pair of injectors or an entire bank depending on whether the valve cover gasket has one or two harness connections.

Service failed connectors using the UVC connector retainer kit, Ford Part number: 2C3Z-14A163-AB. An illustrated instruction sheet from International Truck and Engine Corporation is included in the bag. Use care to avoid breaking the connector!

So what do you look for before getting under the valve covers? If a KOEO self test or Continuous self test DTC retrieval reports a code P1316 (IDM codes detected) then a KOEO Injector electrical self test must be preformed. This is an IDM self test that performs a static test of the module which checks the high and low injector circuits. This test is also called the "Buzz test" because a dynamic test is performed that actuates all of the injectors then retests each injector one by one. If any circuit is found open of has high resistance, a code is displayed corresponding to the affected cylinder. Code output is typically described as: high side open bank 1 or bank two, high to low open injector #1-2-3-4-5-6-7-8. If accessing the IDM and testing all injector circuits from the IDM to each valve cover connector shows no wiring concerns then you must access the valve covers to inspect and test the under valve cover harnesses. If a UVC harness connector if found partially disconnected, use this service kit to restore the locking tab and secure the connector into the valve cover connector. If no connector or wiring faults are found, replace the affected injector and retest the system. Let's take a closer look at the connector in question.

Loose connection - Shown above, the plastic locking tab has weakened and deformed over time allowing the under valve cover harness connector to begin slipping out of the valve cover connector. The picture on the left shows one side is lower causing a low side circuit to fail. In this case injector #8 was affected causing a miss, low power and an illuminated check engine light. On the right you can clearly see that the harness connector is slipping out of the calve cover connector.

Good connection - Below, close-up pictures of the same connector with the retention clip installed as indicated by the yellow arrows. Spring tension has been restored to the clip by the installation of the retainer clip and the connector is fully seated and locked in position.

Some final professional advice: If a repair is made like the one discussed, it is recommended that all electrical connections be restored and the self tests be repeated to verify the repair before putting on the valve covers and restoring the engine to running condition.

FDDTS