James, I was listening to your show last week about “checking for air in the fuel system” in a 2003, 6.0 liter, Ford F-350. I have a similar problem with my 2004, 6.0 liter, Ford F-250 with 247,000 miles. It has a slight engine miss that shows up after it has run several minutes. The truck runs okay other than this.
I heard you say that a faulty injector could allow air to get in the fuel system, causing the engine to run worse. Is this a test procedure I can do with simple hand tools and a couple of balloons? I love my truck, it seems that everything is so expensive to repair on it. If I can save time and money, I’m all for that. -John
Yes, owning a diesel truck can be expensive when it comes to service and repair. These diesel engines are tough workhorses when properly maintained and operated. When they are operated in what you and I would call an extreme harsh environment,they are dependable to operate and maintain (considering what kind of work they do).
When diesel engines are operated in what you and I would considered a normal lifestyle of short trips and going to the soccer games with lots of extended idling to keep the a/c working and the cab cold, problems seem to pop up with more frequency. Every hour of idling a diesel engine is equal to driving 25 miles (as far as engine carbon deposits and mechanical wear and tear). Fuel filters should be changed every 10,000 miles or at least once a year whichever comes first. Oil and oil filters should be changed every 5,000 miles or twice a year, especially on “Power Stroke” diesel engine. They hold a gallon of dirty oil that can’t be removed when changing oil in this engine.
Okay, enough about maintenance on “Power Stroke” diesel engines, here is my modified procedure to determine if you have injectors allowing air to get into the engine’s fuel system.
- Disconnect the fuel lines at the secondary fuel filter. (These are two lines that are going to the right and left side of the engine)
- Put a balloon on each of these two fuel lines tightly with zip ties
- Disconnect the Fuel Injector Control Module also known as the FICM (this FICM looks like a car computer that is mounted on the driver’s side valve cover). You do this to keep the engine from trying to start while doing the next step.
- Crank the engine over for 10 to 15 seconds while watching the balloons tied to the end of the fuel lines.
Did they inflate any at all, even ever so slightly? If so, then at least one injector is allowing compressed cylinder air to be “pushed” into the fuel system. This test only tells you what side of the diesel engine has the faulty injector(s), if both balloons inflate it is both sides. It does not tell you which injector(s) are bad.
Once you have determined which side of the engine has the problem you can have an idea how much time and money may be needed to solve your problem. The average amount of time to do this type pinpoint diagnosis at James Auto Center is 3 hours of labor.
If we may be of service, please don’t hesitate to call James Auto Center of Panama City @ 850-763-0555.