C30 No power up hills
 

I've just bought a 2008 C30 1.6D with 90000 miles on the clock. The vehicle starts, ticks over and runs perfectly with good acceleration and no misfire or uneveness. Unfortunately when climbing hills (even gentle motorway inclines) the speed drops off dramatically often requiring 1st gear just to keep moving. Any ideas please - I'm suspecting fuel filter, but the problem only arises up hills.

Any error codes showing?

If not I would start with a full service including oil, air and fuel filters. May be worth running a tank of premium diesel (shell vpower or equivalent) or a fuel system cleaner through as well along with a decent motorway run in a gear or two lower than normal.

What is the maximum revs you're getting on acceleration?

I'm thinking diesel particulate filter (dpf) being clogged. You should receive an error code for that, and you probably would notice it on the flat BUT it is VERY noticeable on climbs. It depends on what kind of journeys you're doing/how you drive. On around-town runs, it's possible you may not notice it.

You'll not get more than around 4500 rpm with a clogged dpf.

Don't think mine went over 3000 rpm when in limp mode and the turbo seemed to be disabled. As said before, rev it at a standstill..... will it rev over 3000?

check eloys fluid level and dpf pressures