The 7.3 Powerstroke comprises many components working together to deliver the best engine performance. One of the most crucial components is the Injector Control Pressure (ICP) sensor, which helps regulate the fuel delivered to the motor. If this breaks, it can be a massive headache.
Symptoms of a failing ICP sensor on a 7.3 Powerstroke include a stalling or jerking vehicle, a crank without a start, and engine misfires. Replacing a faulty ICP sensor is quickly done with 5/8 and 11/16 wrenches.
This article will guide you on some symptoms of a failing ICP sensor. It will elaborate on how exactly the symptom is produced. The later part of the article will also guide you on how the ICP sensor can be replaced.
1. There Is a Crank but No Start
Cranks require very minimal fuel to work; in comparison, the motor requires a lot. So if your vehicle has a crank, but the motor doesn’t start, that could mean that fuel was not delivered to the motor by the injector.
The ICP sensor is a possible culprit because it regulates the pressure of the fuel going into the combustion chambers. The pressure adjusts according to the driving circumstances.
If oil gets into the sensor and damages its circuits, it cannot provide the proper pressure rating, which it needs to send to the Powertrain Control Module (PCM).
A vehicle’s PCM can be considered as its brain. It works harmoniously with the sensor to determine the correct fuel pressure for optimal efficiency. If a sensor is damaged, it becomes an unreliable fuel regulator for the injector and the chamber.
In some cases, it prevents the passage of any fuel at all. When this happens, it really will become impossible for the motor to start.
It’s also possible that the wiring between the PCM and the sensor is damaged. If this is the case, the PCM cannot communicate the commands for the needed pressure to the sensor. This is why fixing the ICP sensor would often entail checking the entire length of the wire going to the PCM.
2. There Is Engine Misfire
What’s tricky about misfires is that they could result from several components malfunctioning. A misfire can be easily detected when the engine sounds weird or when the exhaust releases thick black smoke.
An engine misfire might result in a temporary stall. In severe cases, your vehicle will decelerate suddenly while you’re driving, so it can be very dangerous if left unresolved.
One of the primary causes of an engine misfire is when the combustion reaction doesn’t work correctly. This could be attributed to an inappropriate amount of fuel flowing through the injectors and onto the chambers.
As you may know, it is the sensor’s job to regulate fuel. If the sensors malfunction, the proper combustion formula for proper engine performance cannot be achieved, causing a misfire.
While it is true that misfires could result from several components malfunctioning, the ICP sensor is integral to the combustion reaction, making it a highly plausible culprit.
It is also possible for your system to interpret a malfunctioning sensor as error P1209 (ICP system fault IPR valve stuck). In some models, the valve brings excess fuel back into the fuel tank.
The system then attributes the faulty combustion reactions to the valve being unable to bring back excess fuel, even when the sensor fails to regulate.
The sensor malfunctioning could also account for sudden rises in fuel consumption. So if you see your fuel meter constantly reading “low fuel” for no apparent reason, it may be time for a sensor check.
3. The Vehicle Is Jerking
A vehicle jerking usually results from an inconsistent amount of fuel powering the engine. Any time the engine receives a fuel surge, it accelerates and stops when the surge ends.
Remember that the fuel pressure is determined by the ICP sensors, and the minute it malfunctions, the fuel flow will become inconsistent. The fuel surge is likely due to the sensors misreading the driving conditions. This then calls for more fuel when there is no need.
It’s also possible for the jerking to happen alongside engine misfires, as fuel inconsistency results in a lot of fuel being unused.
4. The Vehicle Is Stalling
You may start to sense a theme here, with many of the symptoms being caused by the inability of the ICP sensor to deliver the correct amount of fuel. Stalling is very much the result of inadequate fuel in the engine, and the vehicle won’t be able to accelerate properly.
In some cases, the system may detect these as errors represented by code P1211 (ICP pressure above/below desired IPR valves failed, stuck, or shorted to ground) due in part to the lack of fuel flowing in.
5. The Performance Is Faulty in Certain Conditions
Let’s say, for example, you have 300,000 miles (482,803.2 km) on your vehicle. It is very likely that your ICP sensor is not in the best condition anymore. To maintain performance, it’d be best to have the sensor checked every 150,000 miles (241,401.6 km).
A malfunctioning sensor cannot adjust the fuel pressure according to driving conditions. So if your car suddenly starts having performance issues only when it goes uphill, for example, or only if it’s driving over rocky terrain, it may be due to the sensor’s incorrect pressure reading and pressure control.
How To Replace The ICP Sensor
The ICP sensor is usually located close to the alternator in most vehicles. It resembles a short syringe and the tip of the sensor is hexagonal in shape.
A complete replacement should be your last resort. What you can do is check the minor parts of the sensor for the problem — in some cases, you can rectify the issue without a replacement.
Follow the steps below to check what has gone wrong with your ICP sensor:
- The ICP sensor is connected via wires to the rest of the system, so you can begin by checking if there are open or shorted wires.
- Next, check the voltage using a multimeter to see if it matches the 5-volt power supply requirement.
- Check if the ICP passage is blocked by crud and oil. If this is the case, you won’t need to replace the sensor; all you need to do is clean out the blockage.
If you’ve already analyzed your ICP sensor and determined that it can’t be fixed, proceed with the replacement.
Here are the steps:
- Begin by removing connections to batteries or any power source. Working with electric connections is extremely dangerous so ensure you take precautions before starting.
- Clean the threads to make it easier to visualize the sensor.
- You should be able to see the sensor quickly. In most models, the top of the sensor is colored black and is connected to the rest of the system via wires. The base of the sensor is colored gold.
- Unplug the top of the sensor. In a lot of cases, this will be covered by oil. This essentially means that oil has gotten into the sensor, which is why it is delivering inaccurate pressure ratings.
- If the top of the sensor does not have oil, then the problem may be the sensor’s o-ring. Using an 11/16 wrench, tighten the placement of the o-ring. Once done, take the vehicle out for a spin. Proceed with the next steps if the problems persist.
- The tool that would work best for a complete replacement is a ⅝ wrench. Alternatively, you can use an adjustable wrench. Position the wrench on the base of the sensor. Then, with a metal rod, pry the sensor’s base loose by placing pressure on the wrench using the rod and the alternator’s metallic side.
- Once the base is detached, check if the oil has gotten into where the old sensor’s base used to sit. Use a cloth to get rid of all the oil.
- You can attach the sensor’s o-ring using a wrench. An 11/16 wrench, however, is recommended to tighten the sensor in.
- Clean the wires in the connector. They may be soaked with oil.
- Reconnect the connector to the sensor. Take the vehicle for a ride and check the computer for codes related to engine errors. If there are none and no problems persist, you should be good to go.
Once the replacement is complete, I would advise you to keep a spare set of wrenches in a toolbox you take with you in your car.
If you don’t feel comfortable replacing the ICP sensor by yourself, it’s usually recommended to contact a professional to get the job done. If you don’t have the relevant experience, you could end up paying more for repairs further down the road.
Get at least one spare ICP sensor or an IPR valve, as you never know when you will encounter another problem. While you’re at it, save a copy of this article, too, to keep yourself guided!
