Faults:

I bought this one-owner car when it was 5 years old, but it came with a comprehensive service record and receipts, so I can pretty well reconstruct what the original owner experienced:

26/11/13. 0 km. Purchased new

2/10/14. 15,300km. BSI software update.

6/5/15. 23,500km. Check for low coolant level, replaced coolant temperature sensor, fixed defective connection on front headlight.

8/4/15. 40,900km. Note to check/replace timing chain tensioner.

26/6/18. 69,200km. Power loss - replaced high pressure fuel pump and fuel supply rail.

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21/8/18. 69,742km. Purchased by me.

22/8/18. 69,900km. Inlet valves cleaned by walnut blasting, camshaft cover gasket replaced.

12/12/18. 71,900km. Rattle from timing chain on startup. Replaced timing chain guides, timing chain, crankshaft sprocket, tensioner, auxiliary drive belt.

15/4/19. 73,200km. Leaking headlight washer pipe at reservoir – front of car had to be removed. The pipe had been rubbing against the body.

14/9/19. 75,100km. Oil leak from oil filter housing to block and suspect vacuum pump seal.

General Comments:

I bought the DS5 because it had what I desired in a car: head up speed and speed-limit display, turning headlights with corner assist, conventional Japanese design 6-speed torque converter automatic transmission, turbo petrol engine with good torque low down and the promise of reasonable fuel consumption and a tolerance for short distance trips, high driving position and easy entry. But mainly because I was besotted with the styling both inside and out. And at 5 years old it was about 1/3 of the new car price.

Because of the reputation of these direct injection turbo engine in Minis and PSA vehicles, I was expecting the inlet valves to be coked up at 70,000km, and they were. It cost $800 to have them cleaned at a Mini specialist, more than a Mini would have cost because the access to the inlet manifold at the rear of the engine was awful. In retrospect I would have had transparent film fitted to the front panel of the car first to protect it from the mechanics.

In an effort to reduce the carbon buildup I fitted a catch can (Flashlube) to the engine breather hose on the LHS of the engine cover that runs to the inlet to the turbo. This will work best when there is higher air flow into the motor. It seems to be keeping the turbo drier. I also fitted a catch can to the other breather hose on the rear RHS corner of the engine cover that runs to the inlet manifold. However, the Flashlube can was not designed for this application because one of the pressure/vacuum relief valves blew when the manifold was under turbo boost with the engine fumes venting under the bonnet. It worked fine when there was only vacuum at the manifold. I have since fitted a SAAS catch can that has no valves. It is too early to say how effective they are, but they are collecting some watery excrement. The leak from a headlight washer hose gave me the excuse to remove the front of the car to fix it and clean the oil out of the intercooler. And clean the bugs out of it and the A/C condenser, and fit 2mm stainless steel gauze.

The noise from the camshaft timing chain was not a complete surprise, given the reputation of these BMW-designed units in both Minis and Peugeots/Citroens. There were two small plastic lugs broken off the timing chain guides, both lodged in the oil intake grille. What did surprise me was that the crankshaft and camshaft sprockets had no keyways. You have to buy a special timing kit and make sure when you tighten the sprockets against the plain ends of the shafts, that there is no oil present on the faces.

Before I did the most recent oil change I used a can of ThreeBond SA-459 engine conditioner, sprayed down the breather line that runs to the inlet manifold, as an attempt at keeping the inlet valves clean. The engine choked on it a bit, and lit the engine warning light afterwards as a consequence - the light went out after a few drives. I can, of course, detect no difference in performance. I think this is a standard service on direct injection Subaru engines, so it has some credibility?

This was also when I discovered the oil leak that I think is coming from the oil filter housing, where it bolts onto the engine. This was certainly a weak point on our previous 2005 C4, and probably many PSA engines. I will replace both these seals (2 of) and the outer seals where the oil cooler would have once fitted (4 seals). It is a given that the access is awful, but since I also have a MGF I'm not one to complain! I will also replace the brake booster vacuum pump seal while I am at it, but will order all the seals from China and the USA because of the high cost of parts from the local dealers.

While this may sound like a litany of faults, it doesn't stop me enjoying the car. It gives me a very nice feeling every time I drive it. I can understand Citroen purists criticising the ride, but for me it is not a problem. And I can quite understand why Citroen would use a relatively pedestrian platform to keep costs down on what is otherwise a luxurious, well appointed and desirable vehicle. Despite it inheriting the engine faults from its French and German forbears. A diesel would avoid many of the engine issues, but it wouldn't work for me because I do too much short running. And I have more hope of being able to work on a petrol engine. I should add that over the ~5000 km I have driven it is giving 8.4 lt/100km (33.6 mpg) at an average speed of 37km/h, which given the weight of the car and the short trips I do is OK with me.