Hi all, new to the forum but need advice on what might be wrong with my XF, I have a 2014 2.2 rsport xf and it keeps losing power! It will drive fine for like 15/20 minutes and then it loses power struggles to get beyond 2000rpm and won't go higher than 3000. It has no warning lights or anything like that so my mechanic says not alot he can do. Changed the fuel filter around 3 months ago. Anybody have any idea what the issue might be?
Cheers

 

James99, I would assume that your check engine light is on right now. Take your car to a local auto parts store and either ask to rent their code reader or the store will go out and read the codes for you. Write them down (just need the 5 or 6 character code, do not worry about the meaning as the reader will half the time give us Jaguar owners the wrong info). Once you get the codes, post them here. That will tell us a lot about what is going on. Right now, I can blame the problem on about 20 different parts and to tell you "Go replace ......" would be a complete guess. And when some of these parts are $200-300 USD just for the part and then say another $500 USD to install, that gets expensive really fast to see if that fixed it.

If you don't have any warning lights, then what I would tell you to do is to find a road that you are the only one on it and turn on and simply floor the car. This is going to force something to come on on the instrument cluster. If the check engine light starts flashing, then immediately get off the gas to simply allow the check engine light to remain on solid. Then go and get the codes read. If you get the check engine light and when you go to get the codes read, there are none, then you have a problem with your ECU. But, newer cars are pretty good about giving you a code whenever it acts funny like you are seeing.

 

From the hidden menu on the dash I have the following codes:
900A64
900A87
9B3364
9D3615
C10100
Do these codes mean anything to anybody?
Cheers

 

They've accumulated during the life of the car so are by now meaningless.

Read codes properly if you want to know its current state.

 

James, like was said, those codes have been in the car potentially since it was new. I am sure atleast some of them were set as it was going down the assembly line. This is where obtaining the normal ODB-ii codes via the port near the steering wheel is the best thing to do. Some would even say to get them read, clear, drive the car and then let the check engine light come on again so you get the most recent. IT is possible for the check engine light to come on, set a code, and then if the code does not return during the next 5 drive cycles, the check engine light will turn off, but the code is still in the computer. So, that can lead to some confusion if you haven't cleared the codes in awhile. But, we can get past that. Normally you will see the stray code or two as it will not fit with the others that are present.

 

If you're anywhere that does SMOG (or similar) tests, it's best to avoid clearing the codes because it also prevents a smog pass until (or if!) the things cleared (*) have set again. They don't always set again for an age, for various reasons.

(*) mainly the OBD monitors, which must be set in many smog regions

 

I did not know you can read the cars codes without a code reader?
Where is this secret menu?
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Use a smart phone with the Torque app to interface with the vehicle's PCM via a Bluetooth interface plugged into the OBD port to read the stored DTC(s).

List the DTC(s) here to provide a diagnosis starting point.

 

Just to be clear I have no warning lights and I have had it plugged into a diagnostic machine and it comes up with nothing. I gave it a standing start and thrashed it to 80mph earlier today and it still bought nothing up so I am at a complete loss as to what the problem is!

 

If there are no stored or pending DTCs, it's difficult guess what could be causing an intermittent loss of power.

Where is the vehicle operated?

How many kilometres/miles are on showing on the instrument cluster?

Is the engine petrol or diesel?

 

It's a 2.2 diesel 2014 done just over 90k miles

 

Based on the car being a diesel and the nature of the problem, it would almost sound like the waste gate is opening way too soon or there is a hole in the intake. This would cause the amount of air going into the motor to drop significantly, resulting in low power. I am just not sure how that may affect what codes would come up.

 

Would a hole in the intake not effect the power all the time? As I said it drives fine for 15/20 mins then loses the power

 

James, an actual hole in the intake, sure, that would be a problem all the time. But, a waste gate could start having mechanical issues (binding, lack of pull by solenoid, etc) as it gets hot. So, yes, you have the right idea in that it probably isn't a physical hole in the intake, but something on the intake is not playing nice. A random thought that is going through my head is you may have a junction that is slipping as it gets hot. So, as you build boost, it pushes the joint apart, but the suction of the engine pulls it back together. Stranger things have happened.

 

What would you advise I do? By the way thanks for all the replies and thought you have put into this!

 

Not knowing how the intake is laid out, I would see if you can spot the turbo and you should see a bar on it. If you raise the RPMs slightly and then let off, that bar should remain stationary. But, if you see it moving, especially whie you are raising the engine RPMs, problem. I would need to do some looking to learn a bit more about the diesel intake to give more guidance after that.

 

You will have better luck on the UK forum where they had all the Diesels.
It's a good forum too.

UK Jaguar Forum
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I just replaced the coil's spark plugs but then it wouldn't start. I found the previous owner had super glued the fuel regulator fitting onto the side of it, and this was broken. I ordered it and replaced it with a brand-new OEM part. The battery was now almost dead from trying to start the car. I bought a new charger and brought it back to a full charge. IT would spin the motor but it still wouldn't start. Then the security light came on now it won't even crank over. It's a 2005 XJ8L with a 4.2 V8. I am in North Florida USA. I have an ICAR computer OBD2 reader and two original keys. This has me scratching my head and it's starting to bleed...lol PLease help me... some guy named Buster is supposed to be THE GUY. if y'all know him send him my way...

Oh Yeah, I went and ordered the manual from this forum from "eManualOnline" hoping it would lead me to a fix.. nope. that thing reads like stereo instructions...Might as well be in braille....

 

James I have asked already but where is this menu on the dash where your getting error codes?
With the scanners you have are there any current codes?
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