FAQ

The P228(X) codes refer to the PCV or pressure control valve that is on the rail. The location of this PCV varies based on the truck. A LML PCV is on the front of the rail closest to the bump and a 6.7F PCV is on the back of the rail closest to the firewall.

This code means that the PCV is either sticking more open or closed when in operation and this can effect fuel rail pressure and driveability. While this code can typically be resolved by just replacing the PCV itself, it is overall recommended to replace the entirety of the driver’s side rail. The reasoning for this is that the seal between the PCV and rail is a metal to metal seal. If it does not seal properly the issues may be exacerbated.

The PCV must be extremely tight in order to seal and any leak will not show externally; the fuel will leak into the return port. It’s a good a idea to check the tightness of new OEM rails too.

A P0093 code is present when the truck notices that a downstream leak is present within the high pressure fuel system. There are many places for fuel to leak externally, but there are only two that can leak internally.

Internal fuel leaks are leaks that occur when the high pressure fuel is flowing to and through the return circuit when it otherwise should not be. This can occur due to excess return fuel flow from injectors or excess return from a PCV or relief valve.

The best ways to test for excess injector return is to perform an injector return test in the field or to send injectors into us for testing so that we are able to test the return flow. The best way to check for PCV or relief valve excess return is to ensure it is tighten down entirely and in some instances check return flow from the rail to see if there is return at cranking.

This code generally refers to the lack of rail pressure at cranking. A certain amount of pressure is commanded by the ECM and if that is not met (within reason), then the truck will not start. Likely culprits leading to this could be bad lift pump, excess return flow from the injectors or PCV, a bad HPFP, or a bad sensor.

A P0001 code is thrown when the truck notices that the Metering Unit/VCV/FCA is not receiving any signal. This can be due to it being unplugged, not fully seated, or a harness issue. This code means that the pump is running wide open as there is no current to tell it how open or closed it needs to be when in operation.

If fuel filter pressure switch switching frequency > 10, code is set – Indicates low supply pressure. Monitor fuel supply pressure from the lift pump (low pressure fuel system).

Ford’s error code description: “If the location of the gap on the crankshaft sensor wheel occurs at a location on the camshaft sensor wheel that is more than 6 degrees from the expected location for two detection attempts, the code is set.”

If this code is set, it is likely that the truck has a slipped crank gear. This can occur from excessive load on the engine such as aggressive aftermarket tuning.

The DCR needs to be timed primarily due to harmonics. Our goal when developing the DCR conversion was to release a product that was as close to stock as possible, and part of this equation is harmonics. The recommended timing instructions are present for this reason, and we recommend all installers follow the instructions step by step.

The DCR was specifically designed around the Ford 6.7L Powerstroke platform and has not gone through testing for fitment or validation on any other platform at this time.

No, this is not a common occurrence but we do have some helpful troubleshooting tips in the case one of these codes does appear. Please see our FAQ section on ERROR CODES for more information.

No. The Gen2.1 DPK was designed specifically for the CP4 on the 6.7 Ford Powerstroke platform. The DCR is different high pressure fuel pump altogether and does not suffer from the same catastrophic bottom end failures. With that said the DPK is not compatible nor is it needed with the DCR.

Yes. While the DCR was not designed to increase engine power, it does have 25% more displacement than the factory CP4. The increased pump capacity can support more power only if the calibration calls for it. Simply installing a DCR will not increase power.

While it is not a requirement to run fuel additive with the DCR, running a fuel additive of your choice is not going to hurt the pump.

With the 6.7L Powerstroke having a lift pump, the likelihood of air entering the system past the lift pump is extremely slim. This is due to the constant 60 psi that is within the lines that would cause an external leak instead of air suction if a seal were to be damaged or misplaced. A no start after a DPK install is generally broken up into two categories:

The first category is an air lock situation where there is air trapped within the high pressure fuel lines and rails. This air can be expelled by cracking injector lines and running the lift pump. Once fuel begins exiting the cracked fittings, you can then tighten them back down to ensure no more air enters into the system in that spot. Performing this method will help ensure all air is removed from the high pressure fuel lines and rails.

The second category is either an air bubble or piece of debris that has stuck an outlet valve internally within the CP4 that is preventing the pump from generating the commanded rail pressure. This is remedied by taking a long extension, a brass hammer, and another person. The second person would need to crank the truck while the other taps on the CP4 plunger heads with the extension and hammer. This method dislodges the air bubble or piece of debris from the outlet valve allowing the CP4 to operate normally.

At this moment the DPK is only available for the 6.7 Powerstoke market ranging from 2011-2024s with some reports of 2025s as well. We are always looking to expand into new markets that could also benefit from this kit but at this time it is only available for the 6.7 Powerstroke.

This is a good sign of a CP4 failure. In the event of a CP4 failure, the return fuel going through our kit can be heated to higher temperatures than normal. If you find yourself with a melted fitting, it is a good sign that the pump has failed.

Yes, when placing your order through one of our direct dealers use part number CP4-6.7F650-BP-G2.1 and inform them that it will be going onto an F650/F750 so we can make sure to build a kit that is adapted for these trucks.

Our recommendation is to change it at the same time as the other fuel filters on the vehicle. Ford recommends changing fuel fuel filters every 22,500 miles or every 3rd oil change.

If you experience a CP4 failure with the Gen2.1 DPK installed, all you will need to replace is our return side filter and install a new CP4 pump, or upgrade to a DCR pump conversion.

To ensure that the kit did its job, you can inspect the metering unit on the pump; the metering will be clean, meaning any debris made by the CP4 was successfully rerouted to the return side filter. You can blow out the return lines to our return side filter, but any residual debris in the lines will be captured by the return side filter.

Flow relates to the output of the pump while displacement relates to the combined plunger bore and stroke of the pumping heads of the HPFP. The reason that displacement does not equal flow is that they are not linear in scale.

While larger displacement does generally mean more flow, it is not a rule and does not take into consideration other variables such as RPM, pressure, and plunger leakage. Pump flow rate is measured in Liters per hour (L/h) and pump displacement is measured in cubic milimeters per revolution (MM^3/Rev).

Yes, anything diesel common rail we have the capabilities of testing. Just run it by us at info@ssdiesel.com to verify we have the right fixtures to do so or if we need to make something custom in order to test the pump.

No, unlike injectors we do not offer pump upgrading to turn a stock pump into a stroker pump. Feel free to reach out to info@ssdiesel.com with any inquires in the possibility that we can upgrade it.

Yes and no. We build our nozzles and injectors to the nozzle flow percentage over stock standard. This is due to injection duration being a variable that is not constant and is the reason our injector guides show a wide range of horsepower totals depending on injection duration.

With that being said, we can use nozzle flow percentage to estimate the horsepower beyond stock. It varies from engine to engine due to different stock horsepower ratings.

If you’re looking for a 100 hp increase then you need to determine what percentage of the engine power is 100 hp. For example, an early 5.9 Cummins is 305 hp stock. 100 hp is 33% of 305 hp, so you would want 30% over injectors to increase engine output by 100 hp.

Yes, anything diesel common rail we have the capabilities of testing. Just run it by us at info@ssdiesel.com to verify we have the right fixtures to do so, or if we need to make something custom in order to test the injectors.

The percentage over flow numbers of the injectors/nozzles relate to the original nozzle flow rate in cubic centimeters per minute (cc/min) and equate to the percentage increase of the flow rate of the modified nozzle.

IE: 6.7C-100SAC injectors have a nozzle flow of 100% more. 100% over nozzle flow does not equal an exact 100% increase in output of the injector across the board due to variables like rail pressure and injection duration, but it is a good estimate.

It’s worth noting that not that while percentage over sizing has become the industry standard actual output of the injector can vary depending on other internal injector modifications and optimizations. Not all 100% over injectors have the same output.

Yes, with our common rail knowledge and equipment in-house we should be able to upgrade any common rail injector you may have. Just shoot us an email at info@ssdiesel.com to verify the injector and potential for upgrading.

SAC00 injectors should not have an adverse effect on fuel mileage as they are delivering stock quantities of fuel. There are many factors that contribute to fuel mileage, such as operating conditions and overall use of the vehicle.

This situation arises due to piezo injectors requiring back pressure to fire. If actual rail pressure is meeting commanded, it is recommended to either ensure fuel is getting to the return circuit or bumping shop air through the return to build the back pressure required for the injectors to start.

Once the injectors have fired off that initial time, there should not be any other instances where this happens. It only occurs upon the installation since the fuel system was opened up and air was introduced.

A lift pump is not needed when installing a CP3 on the LML. The CP3 has a gear pump on the back that draws suction from the tank. A lift pump is however beneficial in certain troubleshooting situations since it does supply pressure up the pump and any leaks would be external rather that sucking air. Lift pumps may also be beneficial in higher horsepower applications.

YES, this pump is designed to match the flow curve currently within the ECM even if the truck has been tuned already.

The biggest difference will be in the metering unit used on each product. With the No tuning required it will be using a custom metering unit that designed to match the flow curve of the CP4. The Tuning required pump will be using a LBZ based metering unit which will require a pump curve revision within the ECM.

Yes, if you are wanting to run one of our Duramax-based CP3s on a LML Duramax, we will allow you to buy our kit components as a kit paired with whichever size stroker pump you are needing.

The LML did not come from the factory with a lift pump, instead fuel from the tank is drawn to the pump via the gear pump on the high pressure fuel pump. In order for a DPK to work on a LML the fuel flow would need split at the gear pump. With that said, the R&D and overall cost of a DPK for the LML is quickly approaching the price of a CP3 conversion, which is the ultimate solution.

No, there are differences between the RAM CP3 conversion offered by us and the Mopar conversion. The pump offered by Mopar uses a long shaft CP3 and reuses the factory gear. The pump we use is a short shaft and we use a custom gear, pilot and adapter.