Does anyone have any experience receiving both these codes at the same time on an X351? I am wondering if in addition to the vacuum pump (which appears faulty) if the vacuum lines may have cracked or be leaking? I also wonder if the vacuum pump really does often go bad at low mileage (I am only at 35,000 miles in a 2015, 4 Cyl. turbo X351 version) or, if the gasket leaking is the more likely culprit.

I am about to dig in much more tomorrow. Any experience or thoughts would be appreciated.

:-)

 

Hard to say on the 4 cylinders? Do they have the same type of mechanical vacuum pump?
On the V-6 and V-8's it's usually the O-rings and there are 2 known leakers. Pump is pretty reliable.
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My reference shows:

P0299 Turbocharger Underboost Condition

P050F-01 Brake Assist Vacuum Too Low

Leaks would definitely be the first suspects for both DTCs.

Regarding the P0299 code, when inspecting the turbo plumbing visually, any oil leaks will indicate points where pressure is being lost. If you don't see any obvious leaks, a smoke test may be required.

As club mentioned, the vacuum pump O-ring is a likely suspect for the P050F-01. Again, a smoke test can help locate leak points.

Note that many of the inexpensive smoke machines on the market are regulated to 1 psi of pressure for safe testing of the EVAP system, but to test air intakes and turbo plumbing I usually run at least 10 psi and sometimes as high as 20 psi.

Cheers,

Don

 

If i remember right the turbo variable pressure vane is controlled by vacuum operated actuator on the i4 petrol engine. (Same engine used on exsample Mondeo´s, Kuga´s etc..)
Since having both codes vacuum related, i would go thru all vacuum piping, solenoids and actuators. Vacuum pump itself have not been reported as a weak point on Ford 2.0 litre i4 but worth to check out too.

 

Thank you very much gentlemen - you are all very kind !

Will take to my friend and tech now...

I tend to agree about the O rings as the pump failing at 35,000 miles would be unusual. Of note the car did (regrettably) sit out on a dock for 4 or 5 months while awaiting collection in extreme heat - 100 degrees plus at times.... I doubt that did the vacuum lines any good, but more knowledgeable posters than I would know more the effects of sitting outside for a few months in extreme heat.

Thank you - all much appreciated.

 

Take a look at the vacuum pump and check for oil. If the gasket is leaking you usually will also have an oil leak at that spot.
Here is a picture from JPART.



#5 is the gasket and what the diagram does not show is the tubing/hose that connects to the pump #3 has an internal O-ring that JLR does not service separately. But people have removed it and matched the O-ring up.

On the V-8's removing the pump will cause you to lose some engine oil. If you park with the front of the car raised like on ramps. That helps to reduce or eliminate that. Of course you could go ahead and change oil while your in there.
I have an XJR so no experience with the 4 cylinder versions.

Let us know what you find.
It really helps the next guy out!
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OK, thank you for that - very informative. I went back to the tech and he said it was definitely the vacuum pump, as he said when he disconnected the pump it did not make the right noise that it then should. Now that is hardly definitive I know, but I am in a very remote region that has as many techs as your average African country... So the good tech flies in next week and then we will see.

Just for your amusement here is an example of another challenge I am dealing with here. Finally my 2013 V6 X351 is leaking AC. The car has been phenomenally reliable - basically two years needing nothing save the valve cover gasket, alternator and battery at the beginning when I got it. It has literally needed nothing else in 45,000 kms save oil changes and brake pads. So now the fun (stress) starts.... The AC is leaking but no one here yet knows how to find out which valve is leaking. One tech said the expansion valve by the evaporator (yikes), but no tests to prove that assertion, and just a request for several thousand dollars to rebuild the whole AC system after he said it has a leak and a restriction. So when my good tech flies in next week hopefully I will find out for sure, but I have a feeling this could be a bit of a nightmare... unless I am willing to play the role of "OK, please take my $4,000 for the leak and have every part of the AC system replaced...," and then maybe it will work good...

:-)

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I assume he meant that no vacuum was present when he removed the pump, which typically causes a hissing sound as atmospheric air rushes in, but the lack of vacuum at the pump could also indicate leaks elsewhere.

Common methods for locating refrigerant leaks in an A/C system include injecting UV dye into the system, running the A/C for awhile, then using an ultraviolet light (blacklight) to look for any dye that has leaked out. There are also halogen detectors or "sniffers" which can be used, but I have found that often a refrigerant leak is not very active unless the compressor is pressurizing the system, which only happens with the engine running, and the radiator fan(s) tend to cause so much air movement that the halogens blow away, rendering the sniffers useless.

Common leak points include the Shrader valves in the high- and low-side refrigerant ports and the O-rings at any of the refrigerant line connections. Less common leak points are the evaporator, compressor and condenser.

Cheers,

Don

 

Thank you for that information, Don.