Jaguar XF - Intermittent loss of power

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Fri 19 May 2017 19:45
Jaguar XF - Intermittent loss of power - Chris Maitland

For the last few days I've noticed I'm getting an occassional lack of power when accelerating from low speeds. The car feels like it's gone into limp mode. This lasts only for about 2-3 seconds then the cars is off like a shot. No warning lights appear on the dash. Other than this the car appears to function as normal i.e. normal power, no weird noises, no smoke etc.

I'm pretty sure it's turbo related and I've scoured numerous websites but have not found any common symptoms that exactly match mine.

The car is on a 62 plate and annual mileage is about 7500.

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Fri 19 May 2017 20:10
Jaguar XF - Intermittent loss of power - Brit_in_Germany

This sounds like the known "characteristic", especially when moving away at a junction due to the auto gearbox changing down. One solution might be to select S mode or just learn to be more gentle on the accelerator until you are moving above walking pace. The general undertanding in the forums is that it is due to the car normally starting in 2nd unless you put your foot down when it has to downchange.

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Sat 20 May 2017 14:22
Jaguar XF - Intermittent loss of power - Chris Maitland

Thanks for the reply.

Yes I have noticed the particualr characteristic you mention but this is something different. As I've owned the car from new (over 4 1/2 years) I'm pretty sure this is an actual fault on the car.

Just to clarify - the problem I've tried to describe does not seem to happen when setting off from a standstill, it happens mostly when you accelerate from low speed or you hit a steep gradient.

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Sat 20 May 2017 20:54
Jaguar XF - Intermittent loss of power - madf

Sounds like: blocked EGR valve. MAF sensor dirty, dirty air filter etc- none of which will give warning lights.

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Mon 22 May 2017 17:56
Jaguar XF - Intermittent loss of power - Chris Maitland

I had a feeling it was something along those lines.

For the first time the car cut out today. I backed off my drive with the engine cold. Stopped and went to change from reverse to drive and the car cut out. I then selected park to restart but not a thing happened when I pressed start. The ignition was still on, air vents open and a/c running. The start button neither started the engine or turned off the ignition. I got out of the car, locked the door then reopened and the car then reluctantly started. Not sure if this helps with identifying the true fault.

If it's a blocked EGR valave will a cleaner work ofr is this to late?

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Mon 22 May 2017 19:40
Jaguar XF - Intermittent loss of power - madf

Sounds liek a fault with teh ignition control systems .. maybe. I know Jaguar had problems with electroinc throttle assemblies failing ..

EGR valve really needs removal, cleaning and careful examionation. It may be just clogged up with carbon or be worn... £££s then if the latter.

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Tue 23 May 2017 19:21
Jaguar XF - Intermittent loss of power - Chris Maitland

Thanks again.

I'm definitely inclined to believe it's a clogged EGR that the cause.

I'd be interested to know if an independent turbo repair specialist would be a cheaper option than a Jag dealership. I'm sure the latter will not bother cleaning/repairing. They will just replace everything with brand new, at a price of course

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Tue 23 May 2017 20:47
Jaguar XF - Intermittent loss of power - RobJP

Thing is, it makes sense to change the EGR rather than try to clean / de-gunk the old one.

Some cars, it's 2-3 hours of work to swap the EGR. If the EGR itself is £200 or so, then, rather than spending an hour or more cleaning it, then rebuilding everything - only to find the possibility that it still doesn't work - makes no sense. Because if it still doesn't work, they've got to strip the whole job again and THEN replace it with a new one. And you can bet your bottom dollar that the paying customer isn't going to be happy with double the labour bill AND the cost of the new part AND the labour cost for the failed repair.

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Wed 24 May 2017 22:06
Jaguar XF - Intermittent loss of power - TrevL

My experience with this issue for reference. I had similar symptoms, loss of power, rough idle etc. with my 1.6 Suzuki SX4 (175,000 miles). I thought it could be EGR issues and my local mechanic agreed it could well be the case, he has successfully cleaned up EGRs but suggested I get plenty of long runs in to get everything hot for a period as he has seen this help on petrol engines. I had only been doing local run arounds for while, contrary to my usual longer distance work. Work pattern did cnange and long runs did seem to help a bit but I switched to Shell Nitro fuel (might as well give it a go I thought) and it has done a lot of good. I get the very infrequent slight hestitation when cold, but hot running clears this. I'm on ordinary Shell now, I'll see how it goes. If the problem reappears it'll be a EGR clean up job.

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Fri 26 May 2017 09:38
Jaguar XF - Intermittent loss of power - Chris Maitland

What you are saying makes pefect sense.

However just as an update I have tried a fuel additive cleaner and gave it a 100 mile non stop run before going back to my usual short journeys. It may be a bit early to start counting chickens but it actually seems to be working. I've not had any of the symptoms I described since.

I'm not naive enough to think that the internals are sparkling like new but even if it takes a £22 pot of additive every 5000 miles it could be a simpler and cheaper fix.

I'll update when the last of this tank of treated fuel is through.

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Fri 26 May 2017 16:47
Jaguar XF - Intermittent loss of power - Falkirk Bairn

>>even if it takes a £22 pot of additive every 5000 miles it could be a simpler and cheaper fix.

Shell V-Power every fill might be worth a look at.

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Wed 23 Oct 2019 20:44
Jaguar XF - Intermittent loss of power - Jonathan Goad
Hi, Im having the exact same problem you were having. Did you ever get to the bottom of what was happening?
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Wed 23 Oct 2019 20:48
Jaguar XF - Intermittent loss of power - Jonathan Goad

(Duplicate post)

Edited by Avant on 24/10/2019 at 01:13

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Thu 24 Oct 2019 23:31
Jaguar XF - Intermittent loss of power - pd

Is this a 3.0? In which case there are TWO EGR valves - one on each side. They are not actually very expensive to buy but a swine to get to so are not that cheap to replace or remove to clean.

My first port of call would be a new fuel filter if it hasn't had one recently - they seem prone to needing regular replacement.

Really, you need some proper diagnosis with a laptop connected reading all the live data off when the fault appears to find out what is going on. I wouldn't just start replacing random parts without digging deeper.

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Fri 25 Oct 2019 14:31
Jaguar XF - Intermittent loss of power - Brit_in_Germany

The turbo actuator can be problematic on these cars. As mentioned above, a proper diagnosis will aid the identification of the problem. If not at a dealer, you could try a code reader such as the LR II one from icarsoft for older models of the XF. Not sure if it works with the X260.

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Fri 25 Oct 2019 23:23
Jaguar XF - Intermittent loss of power - Jonathan Goad
Thanks thats really helpfull.
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Tue 11 Aug 2020 13:41
Jaguar XF - Intermittent loss of power - N J Clelland

I found this post while looking for possible causes to an intermittent loss of power.

I'd like to try the additive solution before investing in a depressing set of expensive investigations. What's the best additive to buy for this as there are a lot of them on the market.

Any advice greatly appreciated.

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