Fuel Pump Driver Module Symptoms
Jan 14, 2013 Ford F150 Fuel Pump Driver Module Failure Ken Awender. P1233 Ford's Fuel Pump Driver Module.
There are many people who are looking at buying a new truck (New to them!) or considering keeping their old truck for a few more years. Everyone sees these late model F150's with the 5.4L Triton engine as a risky investment but I'm here to tell you this engine can be solid.
It does have some common reoccurring problems you should be aware of. These problems range from easy to change coils, to the dreaded spark plug, all the way to the scary and expensive timing chain issues. This article is mainly written with the 5.4L truck engine in mind, but it also applies to the 4.6L used in trucks, vans, and cars. The most common thing we need to mention, but it is the easiest to fix, is the ignition system. The 5.4L Triton features a coil-on-plug (COP) design; a separate coil for each cylinder that sits atop a specialized spark plug (more on that adventure in a minute! Baotian Bt49qt 20b2 Manually. ). COP systems are now very commonplace in the automotive industry. The general consensus is that this type of ignition system is the most efficient design offering independent control, but the coils do suffer from failures likely related to heat.
Most trucks will need multiple replacements in it's lifetime. The most notable tend to be failures of the coil boot, the piece of rubber that covers the spring that goes from the coil output prong to the spark plug. These deteriorate with age and weak spots in the rubber can cause the spark to jump to the plug well instead of the spark plug. These wells can also fill up with oil or coolant and that can also affect the performance of the coil. Sometimes the can fail internally as well. The most common symptoms of this issue is cylinder misfires under load accelerating or most notably cruising around 55mph in overdrive. It will cause a light jerk or bucking that feels as if you may have transmission issues.
They are pretty easy to replace though. Generally at the Ford dealership, we will diagnose the cylinders with the misfire and replace the plug and coil for those cylinders. Spark plugs are a whole different animal on this engine. They decided to place each of these sensitive coils upon a specialized spark plug that tends to break when removed. Due to the design of the combustion cylinder, essentially these engines are semi-hemispherical, the plugs needed to protrude down through the head to the combustion chamber. The situation is slightly ironic since earlier 2 valve 5.4L (97-03) tended to blow spark plugs out of the head but later 3 valve 5.4L (04-07) tended to break off in the head.
These plugs generally last around 100k miles but they are a bear to remove when you do go to replace them. They have extended sleeves that reside down inside the head that tend to break off because of possible carbon/rust build up. This issue was fixed by a redesign of the spark plug in the 2008+ years.
More details are available in another article I wrote which include step by step instructions on at home. Be wary of driving with this engine if you are experiencing a misfire of any kind. Some people ignore the felt misfire or think it is a transmission issue.
At the dealer, we generally see these trucks go a long time with this misfire condition. Eventually, the truck will start to backfire through the intake and even fail to accelerate to over 30mph in severe cases. If this happens, likely you have a catalytic converter that has been damaged due to misfires. Always be on the lookout if you have a converter failure because engine drivability issues kill catalytic converters. As this model ages, a very common issue in these trucks equipped with a 5.4L Triton 3 valve engine is a failure of the fuel pump driver module. This specific vehicle platform uses a module to control fuel line pressure by pulse width modulation of the fuel pump.
The fuel pump driver module is located under the vehicle exposed to the elements. Specifically, on a F150, it is located above the spare tire attached to the frame. Originally Ford attached the aluminum driver module directly in contact with the steel frame. This led to extreme corrosion build up on the module.
With extended time the corrosion would eat a hole through the aluminum housing and expose the electronics to water and road grime. The module will short out temporarily causing drive-ability issues and eventually could cause permanent damage to the smart junction box.
This usually causes the dreaded code P1233 Fuel pump Driver Module (FDM) Offline. Ford later released an updated replacement (link is for a Dorman part) that comes with mounting studs to space the module away from the frame slightly. The most common symptoms, aside from a no start, is lack of power, the code P1233, and hard starting. Lastly, the scariest part for most late model 5.4L Triton owners, is the problems related to the timing chain, tensioners, and the variable valve timing. When you hear a 3 valve 5.4L Triton running, you generally can tell by the sound of the engine.
Especially on light acceleration most noticeable to the driver with the window down while pulling forward in a drive or down an alley. Most of these issues are caused by low oil pressure do to pump failure or lack of following service intervals, but phasers and tensioners can fail as well. This system is fairly complicated so check out the full description an opperation of the I also wrote a guide to replacement of all these components in another article.
The fuel pump relay is an electronic component that is found on virtually all vehicles equipped with an. It is often found in the fuse box located in the engine bay and functions as the primary electronic switch that controls power to the. The fuel pump relay is usually controlled by the ignition or Powertrain Control Module, and when switched on, will provide current to the fuel pump so that it may function. As the fuel pump relay controls power to the fuel pump, any faults with it can cause issues with the fuel pump, which can cause drivability problems for the vehicle. Usually a will produce a few symptoms that can alert the driver of the issues. Engine stalls One of the first symptoms of an issue with the fuel pump relay is an engine that. If the fuel pump relay has an issue while the vehicle is operating it will cut off power to the fuel pump, which will cause the.
A faulty relay may allow the vehicle to be restarted a short while later, while a completely failed relay will not. Engine does not start Another symptom of a faulty fuel pump relay is an engine that. If the fuel pump relay fails the fuel pump will be left without power. The engine may still crank when the key is turned, however it will not be able to start due to lack of fuel. This symptom can also be caused by a wide variety of other issues, so having the vehicle is highly recommended. No noise from the fuel pump Another symptom that may hint at an issue with the fuel pump relay is no noise from the fuel pump when the key is switched on.
Most will produce a low volume hum or whine which can be heard from the inside the vehicle if listened for closely, or from the outside of the vehicle, near the fuel tank. If the fuel pump relay fails, it will cut off power to the fuel pump which will render it inoperable, and therefore silent, when the ignition is on.
While the fuel pump relay is a very simple component, it plays a very important role in the proper operation of the vehicle. If your vehicle is displaying any of the symptoms above, or you suspect that your fuel pump relay is having an an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the component should be.