After yday getting the car back from the MD having serviced and tried to repair an engine oil leak (oil filter seal), the Engine Management Light Came on. IID says this:

l"System too rich (bank 1) 1/2 P0172-00"

"System too rich (bank 2) 2/2 P0175-00"

Any ideas please/ thanks?

And the answer is:

http://www.obd-codes.com/p0172

Basically this means that an oxygen sensor in bank 1 detected a rich condition (too little 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 P0175, and in fact your vehicle may show both codes at the same time.

Symptoms:
You will more than likely not notice any drivability problems, although there may be symptoms such as a misfire.

Causes:
A code P0172 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 can 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.

• There could be a fuel pressure or delivery problem


Possible solutions include:
• Inspect all vacuum and PCV hoses, replace if necessary

• Clean the MAF sensor. 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 fuel lines for cracks, leaks, or pinches

• Check the fuel pressure at the fuel rail

• Check the fuel injectors, they may be dirty. Use fuel injector cleaner or get them professionally cleaned/replaced.

• Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible)

My next question. Is this one for any competent mechanic with suitable equipment or is it one for a SC Range Rover specialist?

clear the codes - run it for a few days and see if they reappear

IF they reappear - clean the MAF with brake cleaner , takes 10 minutes

I had my mechanics in Nigeria do the following job :

- Clean the petrol tank
- put the new fuel pump in (lucky find by Will, really cheap and he bought and shipped it for me !!). I bought the new in tank fuel filter from my Dutch dealer, was not expensive either.
- clean the fuel lines
- clean the injectors
- clean the inlet manifold

I cleaned the MAF myself.

I did have a K&N filter in it (difficult to get reasonably priced normal air filters in Nigeria) although after the clean up and ECU flash with the latest software (did that with the Faultmate myself) it ran much better and no EML at all.

So bottomline, any indy can do this job, it does take quite a bit of time as there is a lot to remove and clean. So better get an indy that charges decent prices to do this.

Apparently the inlet manifold was quite dirty (and that is why they cleaned it in the first place).

By the way, mine was saying too lean and I did replace all the O2 sensors first, cleaned the MAF and the EML kept coming on until we did the above job. Before I bought my SC, it had not moved for 2 years sitting in the Nigerian heat and I am sure that resulted silicon deposits and other crap in the system. MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

Thanks gents,

Ding - This fault has appeared twice in a week now having first been cleared by the main dealer.

Car was/ is running A1 and so I'll start by cleaning the MAF sensor myself and then if that doesn't keep the warning light at bay, I'll get the rest done by a trusted garage.

Silly question but was it doing this BEFORE it went into the MD for the service..?

If not, could you argue that whatever they did has caused this issue.? Then it would be up to them to resolve Ash
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Hey Ryan, apart from the EML on occassion (usually during "spirited driving") it ran fine, not great mind you. It always sounded "not super smooth" before we did the big cleanup.

Afterwards though it was super silky smooth and no matter how "spirited" the driving got, no EML. The ECU flash with the latest software (mine was for sure on the 2005 original software version) has helped as the original software had some very "narrow" margins of error apparently. But the total clean up of the fuel system and inlet tract most definitely helped with the smooth running.

If we move to a place where I can easily bring the 4.2 into the country I may even keep it as a "fun" car (off roading/dune bashing type work) and keep the 5.0 as my daily driver. But no idea where we are / I am going next (oil industry job finding is a bit slow due to the oil prices) or whether we stay in Malaysia (and I work here or go on rotation). Anyway, the 4.2 is still a brilliant car and can run extremely well with sufficient TLC. In other words, I would invest in some manhours cleaning the fuel system and inlet tract as well as making sure the ECU of the motor management and gearbox are given the latest software . MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

Comports,

You pose a reasonable question.

Last edited by pld118 on 15th Feb 2015 5:46am. Edited 1 time in total

Cheers Eugene, that's really helpful.

I will invest in having this fixed quickly.



Last edited by pld118 on 15th Feb 2015 5:46am. Edited 2 times in total

Good luck mate. By the way, because the inlet manifold is taken of, new gaskets are needed as well. Dan can probably do you a good deal (they weren't expensive from the Dutch dealer either). MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

one helluva coincidence that they had the engine out and now running rich

good luck with it but I'd say its worth asking them to have a looksee - went in running okay comes out running rich and the history of previous errors they have made who's to say they haven't up again.

start looking for another dealer IMO

It may seem obvious but take Airbox Cover off completely before disconnecting then removing the MAF Sensors. The bolts are very difficult to get at in situ...

Halfords Electrical Connector Spray Cleaner works well.

Thanks Gary, I also just found a helpful online you tube video of an American chap removing and cleaning MAF.

Took Gary's advice and bought the Halfords Electrical Contact Cleaner, linked/ pictured below.

Such an easy job to do on the SC. On the SC, the MAF sensor is visible and accessible to the right hand side of the RHD engine bay as you look at it from in front of the grille. Undo 2 x T20 size Torx screws with a T20 Torx socket, lift the MAF out of the housing chamber it sits in and then unplug the connector. Generously spray the contact cleaner onto the MAF and into the MAF chambers. I then left it to air for 30 minutes to ensure the evaporating cleaner had fully dried. Then refit the MAF sensor.

Apparently this job should be done every time the car is serviced. I don't think it has ever been done on ours before.

Having done it, the car started more crisply, the idle calmed down a bit and dropped slightly and the car seemed more settled on a long drive today.

I've also bought Millers Oils "Petrol Power ECO MAX" to use next time I fill up to clean the injectors (link and photo at foot of post).

http://www.halfords.com/motoring/engine-oi...aner-400ml

Click image to enlarge

Click image to enlarge