b"Ok, the battery passes the load test and has enough voltage to support the vehicle startingand Fuel Pump Duration. and running the vehicle electrics. Let's move on. Armed with your quick test information, aWhatisfuelpump quick read will allow you to focus on possible causes for poor engine performance. P0300,duration? It is the actual P030-1,2,3 etc. In this scenario we have a running vehicle with mis\x1eres. So, let's look at the fuelamountoftimethe (system). high-pressurefuel pumpsareatfulllift. The most common power plants for this type of Range Rover vehicle are a 5.0 liter,Looking at the data PID Naturally Aspirated (NA) engine, or 5.0L Supercharged (SC) in our case. A good next steponyourscantool(PID would be to test fueling performance using our scan tool. 22), this duration reading should be between 8-12 The 5.0-liter NA engine, as well as the 5.0 Supercharged (SC), 3.0 SC and 2.0 turbo enginesdegrees.Something use a high-pressure fuel system. The 5.0 NA ,5.0 SC and the 3.0 SC have Two high pressurehigher could indicate the fuel pumps attached to the side of the block. (2.0 Turbo has a single HPFP) both fed by apump duration request is Low-Pressure fuel system, consisting of an in-tank electric fuel pump controlled by a fuelexcessive.Lowfuel pump driver module. pressure can be a cause for a lean run condition. Using your scan tool, select the correct area to show you fuel pump data. With the key on andThePCMwillinterpret engine o\x1f (battery maintainer connected) view the information shown.low fuel pressure as lean fault and increase the duration to compensate for this lean condition. Typically, the \x1erst thing you want to know is the actual in comparison to the command fuel pressures. Some tools call the command pressure the desired fuel pressure. With The key onThe High-Pressure twin fuel pumps are driven by their own separate camshaft. This Camshaft is and engine o\x1f you will be abledriven by the engine crankshaft via separate timing chains (Two). It is not uncommon for the two toseethecommandpressureshaftstobecomeoutofsyncduetoaweaktensioner.Thiswillcauseanotherbitof reading. This is what the PCM isdisinformation to the PCM, a\x1fecting the mixture control (mis\x1eres). Checking the fuel pumps callingforandtheHPFPswill require some additional diagnostic time and special timing tools, so before going that route shouldbeabletosupply. Theits best if we leave that \x1enal check to con\x1erm our suspicions. Let the data collected decide if actual will be zero or very lowthats the next course of action. Follow the manufacturer's work instructions for your vehicle and (theengineisnotrunning).Acheck timing if required. basereadingof10MPa (Megapascal)willbeyourWhat about fuel conditions? Before we condemn a pump, or spend additional time checking command pressure shown. Thistiming, my recommendation is taking a fuel sample. Many of these vehicles sit for long periods is equivalent to 1450.00 psi. So,oftimeandcomeout were dealing with a lot of fuelduringSeasons.A pressure.Itshouldbeobviousc o m p r o m i s e d thatplacingacommonfuelEvaporativesystem,bad pressure gauge on the rail is notorstagnantfuel,and agoodidea.Yourgaugewillhighethanolcontent explode.Thesefuelpressurecould draw moisture out readingsarebestreadwithaoftheairwhilethe pro\x1ecient scan tool. vehicleshavebeen sittingunused.(Water The other set of fuel pump datadoesntburnwell). willbefromthelow-pressureCheckingfuelcondition sideofthings.Firstly,thereisquickandshouldnot shouldbeadataPIDforlowbeoverlookedwhen pressure fuel pump duty cycle,dealingwithrandom typically about 10% - 35% depending on the request. Then low-pressure fuel pump actual value,mis\x1eresandhardstarts. typically 549 KPa. Especiallywithvehicles that sit for long periods Now start the engine, the actual rail pressure should raise to a minimum of 10 MPa and higher.of time.Morelikelysomewhereabout12-14MPa.Inourexampleimagelivedatashows9900.00 Kilopascal or 10MPa. This is an indication that the HPFPs are capable of producing correct fuelWorking our way through our road map, we have ruled out many of the basics such as we pressure. However, it is a common fault that the HPFPs will make good pressure at \x1erst, thenmentioned in this article, a few additional checks, such as vacuum leaks, ignition (Spark), and diminish to a pressure that is unable to keep the engine running (engine stalls). So, watch thesedont forget the silent performance robber, carbon build-up.pressures for several minutes. The low side should raise to 749 KPa with the engine running. This is equivalent to 108.00 psi. Carbon build-up on GDI Direct engines is becoming more relevant and more di\x1dcult to detect. Vehicles have become very good at masking carbon build-up through engine adaptations, As you watch the command or desired pressure, with the engine running, you will notice that theignition timing, and fuel delivery. A good inspection camera will come in handy to verify carbon reading has dropped to zero. This is correct. The initial command pressure is like an enrichmentbuild-up on the back of the intake valves. feature (in the old days this was called a choke). It is designed to allow enough fuel to enter the engine upon initial startup and cold running events. The low side readings should remain at 749In this article we have discussed a few possible reasons why Jaguar and Land Rover engines KPa.could be mis\x1ering and stalling as well as a few JLR actual values, and tips to help you diagnose drivability issues in your shop. Develop your plan, follow the road map, and become comfortable Any inconsistencies in the HP fuel delivery can confuse the command from the PCM. Incorrectwith the data in front of you to drive each test. Based on the data provided, it looks like our data will result in an incorrect fuel mixture. Keep an eye on Fuel Rail Sensor, Low Side, High Side,High-Pressure Fuel Pumps are the culprit and will need to be replaced and retested. iscantech.com28"