Solved: Mystery misfire on Ford Transit

April 18, 2024

With 260,000 miles on the odometer, the reasons why this 2015 Ford Transit were misfiring could seem nearly endless.

A repeat of a failed test (once the repair has been completed) is always a great idea. This No. 6 injector cancellation exhaust gas test proves the fault has been repaired, with the replacement of the GDI injectors.

In a recent case study for the Data Doesn't Lie, Motor Age Technical Editor Brandon Steckler was helping another technician determine why a 2015 Ford Transit with a 3.5L V6 engine and a gasoline direct-injected fueling system was misfiring.

Initially, it was determined cylinder No. 6 was the problematic cylinder, and that the misfire only happened under heavy engine loads above 65%. Get reacquainted with all the details of the 2015 Ford Transit here.

Here are the four options Steckler presented as possible options for the fix. Which did you choose?

Replace all six fuel injectors to be sure.
Replace the No. 6 fuel injector only.
Evaluate the performance of the injector circuit.
Perform and injector system cleaning service.

For those of you who chose answer No. 3, congratulations. The amperage waveform is frequently one reflected upon to determine if/how the work is being performed. It will be clear to see if the injector is not functioning properly but also determine if the circuit is functioning correctly. Although the test was conducted the injector drive circuits were all identical, eliminating the circuitry and PCM as the fault.

The next logical thing to do might be to perform an injection/induction system cleaning service but results vary so I won't say answer No. 4 is incorrect. Although it may be cost-effective to replace only the faulted injector, the labor is very similar to replacing all six. Even If we educate the customer about the fact that the other five injectors are of the same age and operated under the same conditions, it will be up to them how they wish to proceed in that fashion. This customer agreed to replace all six injectors and the drivability fault was rectified (See the image).

Motor Age Technical Editor Brandon Steckler presents a new Data Doesn't Lie challenge every month.

About the Author

Brandon Steckler | Technical Editor | Motor Age

Brandon began his career in Northampton County Community College in Bethlehem, Pennsylvania, where he was a student of GM’s Automotive Service Educational program. In 2001, he graduated top of his class and earned the GM Leadership award for his efforts. He later began working as a technician at a Saturn dealership in Reading, Pennsylvania, where he quickly attained Master Technician status. He later transitioned to working with Hondas, where he aggressively worked to attain another Master Technician status.

Always having a passion for a full understanding of system/component functionality, he rapidly earned a reputation for deciphering strange failures at an efficient pace and became known as an information specialist among the staff and peers at the dealership. In search of new challenges, he transitioned away from the dealership and to the independent world, where he specialized in diagnostics and driveability.

Today, he is an instructor with both Carquest Technical Institute and Worldpac Training Institute. Along with beta testing for Automotive Test Solutions, he develops curriculum/submits case studies for educational purposes. Through Steckler Automotive Technical Services, LLC., Brandon also provides telephone and live technical support, as well as private training, for technicians all across the world.

Brandon holds ASE certifications A1-A9 as well as C1 (Service Consultant). He is certified as an Advanced Level Specialist in L1 (Advanced Engine Performance), L2 (Advanced Diesel Engine Performance), L3 (Hybrid/EV Specialist), L4 (ADAS) and xEV-Level 2 (Technician electrical safety).

He contributes weekly to Facebook automotive chat groups, has authored several books and classes, and truly enjoys traveling across the globe to help other technicians attain a level of understanding that will serve them well throughout their careers.