Jaguar XF 3.0 V6S diesel showing Restricted Performance.I have cleaned the mass air flow sensor as I had an error code showing this. If the engine is turned off the warning goes away. Help please.

Unfortunately this is a well known issue and well documented.

https://www.google.com/search?q=2010+Jaguar+XF+3+liter+Diesel.+Water+in+diesel+warning+light

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have the OBD codes read at a jag dealer this should give you the solution , probably a sensor(s)

Check the water proof covering of all the wiring connections as there is one that has failed and allowing water into the connection when it is wet . Seal with spray wax after drying out the connection

P0102 - Mass Air Flow Sensor Circuit Malfunction

The mass air flow or MAF sensor is placed in the intake air duct between the air filter and the engine intake manifold. The MAF sensor measures the amount of intake air flow. The MAF sensor converts the air flow measurement into a voltage or frequency signal, with the voltage or frequency changing proportionally to the amount of air flow. The air flow sensor signal is monitored by the engine computer (ECM). The engine computer (ECM) uses the mass air flow signal to know the engine load and to calculate the proper amount of fuel injected. If the signal from the mass air flow sensor is out of expected range, the ECM detects a fault and sets the code P0100. For example, the mass air flow sensor signal could be higher than expected when the engine is not running or lower than expected with the engine running. A car with the code P0100 may have some driveability issues, such as stalling, lack of power, surging, hesitation, etc. In some cars, the code P0100 can cause the fail-safe mode where the engine speed would be limited to 2,500 - 3,000 rpm.
If there are other trouble codes present, they might need to be looked at first. Checking the freeze frame may help, as it may contain some important information. The freeze frame is a snapshot of the engine parameters at the moment when the fault was detected. The freeze-frame may show whether the vehicle was running or stopped, whether the air-fuel ratio was lean or rich, was the engine was cold or warmed up at the time of the malfunction. Read more about the freeze frame.

Read more about mass air flow sensor.

What could cause the code P0100:
- faulty or contaminated mass air flow sensor
- open or short in the mass air flow sensor electrical circuit
- open or short in the sensor power or ground circuit

- other electrical problem with the MAF sensor wiring, (corroded wires, bent terminals, bad ground connection, burned fuse, etc.
- vacuum leaks
- restricted air flow at or before the air filter
- wrong air flow sensor installed
- problem with ECM

P0102 - Mass Air Flow Sensor Circuit Low

The mass air flow or MAF sensor measures the amount of air entering the engine. The engine computer (ECM) uses the mass air flow signal to calculate the amount of fuel injected (read more how the MAF sensor works below). The code P0102 is set when the signal from the mass air flow sensor is lower than expected. Often a car may exhibit some driveability symptoms, such as lack of power, surging, hesitation on acceleration, hard starting, pinging (detonation), or rough idle when started cold. Often the codes P0171 or P0174 could also be stored along with the code P0102, as the incorrect air flow signal can cause the engine to run lean. The codes P0171 and P0174 indicate a lean condition. Checking the freeze frame might help in the diagnostic process. The freeze frame is stored in the ECM along with the trouble code. The freeze frame contains some recorded parameters (e.g. vehicle speed, engine temperature, fuel trim) at the moment when the fault was detected. The freeze frame can also be accessed with a scan tool.

What could cause the code P0102
- faulty or contaminated mass airflow sensor
- debris blocking the air flow at the mass air flow sensor
- unmetered air leaking past the MAF sensor (vacuum leaks)
- PCV system vacuum leaks
- restricted or collapsed intake air duct
- dirty or restricted air filter
- restricted air screen before the air filter
- improper application of aftermarket components (e.g. cold intake, modified air filter, etc.)
- wrong air flow sensor installed
- electrical problem with the MAF sensor wiring, connector, power supply or ground.
- problem with ECM
- in some cases other issues with the fuel injection system like a clogged catalytic converter or a faulty manifold absolute pressure sensor (MAP) can also cause the code P0102.

Solution for MAF repair

I found a YouTube video, MAF Sensor Cleaning in Slow Motion-rzrDIRZ-ccs.webm, that showed me how to remove the mass air flow sensor and spray clean it with CRC mass air flow sensor cleanser. I bought the kit (single use of Mass Air Flow Sensor Cleaner and Throttle Body and Air-Intake Cleaner at Walmart for $7.99 in store price) and cleaned the mass air flow sensor. Then I reset the check engine light by removing and replacing the negative battery terminal. It worked. The check engine light has stayed off. I have a 2005 Toyota Matrix.

P0100 NISSAN - Mass Air Flow Sensor Circuit Range/Performance Error

Possible causes- Dirty mass air flow sensor
- Dirty mass air filter
- Mass air flow sensor harness is open or shorted
- Mass air flow sensor electrical circuit poor connection
- Intake air leaks
- Faulty mass air flow sensor
Tech notes Before replacing the mass air flow sensor, try replacing the air filter and cleaning the air flow sensor with low compress air or mass air flow sensor cleaner. Reset code and drive vehicle. If the code comes back, it may be necessary to replaced the mass air flow sensor.

P0101 ISUZU - Mass Air Flow Circuit Performancehttp://engine-codes.com/p0101_isuzu.htmlForum CodePossible causes- Dirty mass air flow sensor
- Dirty mass air filter
- Mass air flow sensor harness is open or shorted
- Mass air flow sensor electrical circuit poor connection
- Intake air leaks
- Faulty mass air flow sensor
Tech notes Before replacing the mass air flow sensor, try replacing the air filter and cleaning the air flow sensor with low compress air or mass air flow sensor cleaner. Reset code and drive vehicle. If the code comes back, it may be necessary to replaced the mass air flow sensor

I had the same problem. Restricted performance and running rough at 3000 RPM. I have an OBDII code reader and found that the problem was in the air mass flow sensor, which is just after the air filter. I pulled this out and found it was dirty and had butterfly wings in it. The last shop where I had the oil changed replaced the filter for me but put in the wrong size. Close but no cigar. Bought some *** Flow Sensor cleaner at auto store and fixed the problem. Get an OBDII reader with the ability to erase the codes. Comes in real handy.

You need to take to Jaguar technician to have Mil lamp codes read and cured the restricted performance is the engine protecting itself as there is a fault in the management system,usually fuel system related,It has gone into "Limp Home" mode to try to limit the damage done untill the fault is cured

I had the same problem on my 1998 XJ8. My dealer told me it was the Mass Airflow Meter, which needed replacing to the tune of around $500. After a second opinion at my local Jag mechanic, it turned out to be a hose that was broken on the lower part of the front of the engine. Check the vacuum hoses for breaks or loose fittings.