The Ford Powerstroke 7.3L is known for using a highly sophisticated, hydraulically controlled fuel injection system, known as HEUI, to deliver fuel to the combustion chamber, which powers the engine. The injection control pressure (ICP) sensor plays a vital role in this process. It measures the pressure of the oil in the fuel injectors to make sure the engine will receive enough pressurized fuel to power the engine. The sensor stays in constant communication with the rest of the HEUI to keep everything running smoothly. But the average stock ICP sensor will likely fail sooner than expected.
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What Is an ICP Sensor?
The ICP sensor is a small electrical component that records the current PSI of the oil in the fuel injectors. It sends a five-volt signal to the powertrain control module (PCM) in a continuous loop. The PCM will then adjust the amount of oil in the fuel injectors using the injection pressure regulator (IPR) valve based on the amount of fuel needed to power the engine. Sounds pretty simple, right?
But the ICP sensor is subject to fail. When the sensor can’t accurately report on the amount of oil in the fuel injectors, the PCM can’t regulate the amount of fuel going into the engine, which can lead to a range of problems behind the wheel. A faulty sensor can damage various components in the engine, increasing wear and tear. Your injectors, high-pressure oil pump, and other components related to the oil supply will likely fail as well, so you will need to replace your diesel parts more often than expected. Symptoms range from rough riding to frequent stalling — if your vehicle even starts at all. Keep these warning signs in mind to fix your ICP at the first sign of trouble.
Warning Signs of a Bad ICP Sensor:
Rough Idling
You’re bound to notice more bumps and sputters than usual when the ICP fails to do its job. This problem tends to be more apparent when you’re idling because the PCM is having trouble maintaining constant oil and fuel pressure to keep the engine running. The HEUI could be injecting too much or too little oil for the fuel injectors to supply enough power to the engine.
Hard Start
You may notice something similar when you try to start the engine. The vehicle needs a certain amount of fuel to turn on, and the ICP may be causing some interference. You can quickly find out if your ICP is the cause by removing it when the engine is off. Try starting it again to see if that solves the problem. When the ICP is out, the IPR valve will default to its normal settings to increase oil flow.
Poor Fuel Efficiency
The PCM directly controls how much fuel is being consumed by adjusting the amount of oil in the injectors that fire fuel into the combustion chamber. If the ICP sensor is acting up, the PCM won’t be able to regulate the amount of fuel being burned based on the current rotations per minute of the engine. Expect to burn through more fuel than usual as the PCM tries to overcompensate by burning more fuel than what’s necessary to power the engine. Considering most ICP sensors only cost around $100, it is wise to replace your faulty sensor before you start losing fuel efficiency.
Frequent Stalling
The engine will stall if it doesn’t have enough fuel to generate power. If your truck stalls, it could mean the PCM isn’t supplying enough oil to the injectors to fire fuel into the combustion chamber. The PCM tends to overcompensate for a faulty ICP sensor, so your vehicle shouldn’t stall due to a bad sensor unless you continue to neglect the problem. Remember that the ICP needs at least 500 PSI to fire. Anything below that will result in a dead engine.
Check Engine Light
Expect the check engine light to come on as well when the ICP sensor fails. Check the code listed on the CEL and check your owner’s manual to find out what it means. The following codes are related to the ICP:
- P2284 – ICP circuit performance fault
- P2285 – ICP signal too low
- P2286 – ICP signal too high
- P2288 – ICP overpressure
- P2289 – ICP overpressure engine off
- P2290 – ICP under pressure
- P2291 – ICP under pressure while cranking
A bad sensor can also lead to increased oil consumption. Expect to go through your oil supply faster than normal as it continues to fill with soot, ash, and other debris. Be sure to change your oil regularly to keep your injectors working properly. Unfortunately, many of these problems can also be caused by other mechanical issues. For example, you may need to replace your EGR coolers if your fuel efficiency drops, or the engine is having trouble idling.
The ICP sensor is one of the most important — and yet overlooked — components in a diesel engine. It is tied to the amount of fuel you are using at any given moment. However, the ICP tends to be problematic on the 7.3L Ford Powerstroke engine. Find a replacement ICP sensor for the 7.3L to fix the issue.