P0171
Info supplied by PERMOVEO via Google
Hi
Anybody tell me where the maf(mass air flow) sensor is?
Code is saying is is dirty/faulty and cleaning it usually resolves prob.
Not being mechanically minded, I wondered what sort of job this is for a jag dealer?
Cheers
Brian

 

P0171 is Bank 1 combustion too lean
Engine misfire
Causes
Air intake leak between MAF Sensor and
cylinder head
Fuel filter / system restriction
Fuel injector restriction
IP Sensor fault (low fuel pressure)
Low fuel pump output
HO2 Sensor(s) (1/1, 1/2)
harness wiring condition fault
EFT Sensor fault (low fuel temperature)
MAF Sensor fault (low intake air flow)
Exhaust leak (before catalyst)
ECM receiving incorrect signal from one or
more of the following components:
ECT Sensor, MAF Sensor, IAT Sensor,
IP Sensor, EFT Sensor, TP Sensor

so it could be all manner of things. Bank 1 only suggests an O2 sensor.

Cleaning the TPS is easy and will do no harm. At the same time check for leaks in the air inlet tract.
Doing a search for TPS cleaning will give you the info you need for that.

Have you got your own OBD reader ? If so does it do fuel trims?

 

+1 I'm with steve, get an obd2 reader and watch the life fuel trims. Even if bank 1 was triggering the lean code, that doesn't mean that bank 2 isn't right behind it. Observing the data live is the only way to know. Most of the obd2 units do not measure the voltage output of the upstream sensor, which is what tells the ECM if you have too much or too little oxygen in the exhaust. It has a baseline value (1.0v IIRC) and anything too different from the other sensor on the opposite bank will lead you to a sensor failure. If the downstream sensors are both equal (roughly) the cats are good, and sensor is suspect. If the downstream is high, then that cat is probably clogged and toast, and no amount of fixing things upstream are going to remedy it.

 

Borowed OBD from friend

This is what I read on line



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Jaguar > OBD/DLC Diagnostic Trouble Error Code > P0171




Vehicle Manufacturer: Jaguar Cars Ltd
Established: 9/11/1922
Country of Origin: UK



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Generic OBD Error Code Details for P0171


System Too Lean


What does this mean?

OBD Code P0171refers to
Basically this means that an oxygen sensor in bank 1 detected a lean condition (too much oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1. Note: This DTC is very similar to P0174, and in fact your vehicle may show both codes at the same time.
Symptoms

Possible sumptoms of OBD code P0171
You will more than likely not notice any drivability problems, although there may be symptoms such as a lack of power, detonation (spark knock), and/or a hesitation/surge on acceleration.
Causes

Possible causes of OBD code P0171
A code P0171 may mean that one or more of the following has happened: •The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters may cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry. •There could be a vacuum leak downstream of the MAF sensor.
Possible Solutions

Possible solutions include: •In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling •Inspect all vacuum and PCV hoses, replace if necessary •Check for a dirty fuel filter and proper fuel pressure

 

It's in the Inlet Trunk next to the Air Filter (arrowed in red):



This is what it looks like off the vehicle:



Graham

 

+2 on Matt's summary.
If you look in the HOW-TOs in this section you can download JTIS for your car.
This contains the MY specific DTC codes for your car, complete wiring diagrams and a very comprehensive manual.
You can get a bluetooth OBD adapter from EBay UK for <£10. You pair it with an Android phone running an app called Torque and you can then read off the things Matt (H20 boy) mentioned.
By all means clean the MAF and check for leaks but you will need your own code reader with this car.

 

Thank you guys for all your helpful advice.
Being a mechanical dummy, I booked it in with the local Jag dealer, I have got to know the manager who says he can resolve it in under an hour, so I am taking it ih Thursday....I will let you know the outcome, hopefully, the problem will be resolved as the car appears to drive normally.....appreciate your advices....Brian

 

OK guys
As suspected, MAF sensor~lean mixture

They cleaned up sensor and connected to SDD and cleared codes.

Job done

Thanks for your advices

Brian

 

I recently had a similar problem with my 2001 XK8 with the same code. I removed and thoroughly cleaned the mass air sensor which only briefly solved the problem. Replacing this sensor with a new OEM sensor solved the problem. Removing the sensor is an easy process.