2006 Sport. Problem - lack of power?

Just driven from Northern France to Southern Spain.
 
Roads going across the Spanish Plains - one road 177 miles long  -light traffic, ideal for "cruise control" set at 120k.  On all the long inclines speed not held, engine did not change down to maintain set speed.   Depressing the accelerator did not increase speed and "kick-down" did not change down.   Putting the stick across to manual and coming down a couple of gears did result in being able to maintain and increase speed and revs - up to 4500 without any problem before automatically changing up a gear.
 
Going across the Pyrenees the car wouldn't accelerate up gradients to maintain or increase speed.  Kick Down did not work.  The only solution again was to go into manual and drop down a couple of gears and accelerate.  Went into "limp mode" once. 
 
Just driving around towns and in general there doesn't seem to be a problem. It performs as normal when given a hard acceleration from a slip-road onto a motorway.
 
I think I have ruled out a duff delivery of fuel? - there is no indication of pinking.

Car - fully laden equivalent of 4 normal size adults.   Fuel - Total premium diesel. 

 
Hopefully I have explained the problem for someone to come up with possible cause?    Would be appreciate comments!!...….would hate to be caught out on any of the long exposed Spanish roads or, heaven forbid, in one of the tunnels on my way back home.
 
 
 
 
  Andrew Kennedy

I don’t think cruise control should make it change down ? And drive fast up hills ? Or do you know it’s capable of that ?

What fault code did you get ?

Egrs blanked?

Hi Andy - I didn't receive any fault codes on the dash. I do this France to Spain trip every year and haven't had this problem before. Usually going up steep hills in cruise control it would change down at some point to maintain the set speed. Could the problem be something to do with torque control? My concern is whether I need to have it sorted before the return trip - hopefully not!! Andrew Kennedy

IF you have a fault code reader, read them and clear them.

I don't have a fault reader. I have just looked online and can see its a handy gadget, however, my knowledge and understanding of car mechanics is nil. If a code reader told me what that problem was, I doubt I could do anything about it - changing the air and pollen filter is about my limitation - unless its something practical.

I suppose I was hoping having explained the problem in some detail, someone might have come up with the possible cause of the problem and either suggested I get it looked at......or......say its not a serious problem and one that can wait until I get back to base after my holiday. Andrew Kennedy

Andy - perhaps I missed the point - if I were to get a code reader, should I had a problem in the future, with the code someone on the forum might be able to tell me what the problem was. I can see there are various on the market, can you suggest a model that would best suit a 2006 Sport. Andrew Kennedy

Exactly. If you had yellow lights or messages on the dash it could have logged a code.

For you I would recommend an autel ap200 in white. (For use with smart phone)
Look on Amazon eBay in France. Older models are better.

Decent gap ones cost £500 but you won’t get the benefit

i got a used Icarsoft one off marketplace for £50, works spot on for what i need it for.

Lack of power or lack of downshifting is the real question here. The fact you whacked the accelerator and the trans didn’t kick down makes me think you need to be looking at the transmission. Have you ever had it serviced? May have a dead/clogged solenoid that’s not doing its job. 2011 RRS HSE Luxury 3.0 TDV6 Fuji White on Ebony/Ivory
Born and raised in So Cal. Moved to the UK in 2018 for a few years. Now in Poland and looking at moving back to the UK.

Thanks for yous No Expert! Frankly I don't know if the transition has been serviced. I take the car in every year for a general service - when I get back from holiday I'll take it in to be looked at.

I have a 800 miles drive (over the pyrenes) to get me home and I can see I am going to have problems with the power. I can relate to your suggestion of the possible problem. If that is the problem, would I be correct in thinking I shouldn't have any power problems if I use the manual shift down through the gears when extra power is needed?!? Appreciate you comments. Andrew Kennedy