Owning a car with Ford / Peugeot 1.6 TDCi / HDi engines.

The merits or otherwise of owning a car powered by the DV6 diesel engine (Ford 1.6 TDCi, PSA 1.6HDi, Suzuki 1.6DDIS etc etc) have been discussed ad nauseum in this and many other for forums. In particular, these engines do not tolerate neglect or improper servicing, which can lead to oil-ways becoming clogged, which in turn can starve the turbo of oil and even write-off the engine itself. It's shame really because these engines otherwise perform strongly with good fuel consumption, and in our case, quite good reliability too.


My wife has been the owner of Ford C-Max which has one of these engines (110 BHP with a DPF ) for several years now, and mindful of the problems these things can face, I've outlined where I believe the weaknesses lie and the steps that can be taken to mitigate them. During a recent oil change I took the opportunity to grab a few pics to help evidence the opinions and theories I have.

To give this some background, these engines run fairly hot and especially so if it has a DPF. The DPF regeneration process superheats the DPF to somewhere between 500 and 600 degrees centigrade by means of addition fuel injected during the exhaust stroke, the energising of the glowplugs and the EGR valve remaining closed. An additive called EOLYS is added to the car's diesel from a secondary tank each time you fill up at your local station. This additive lowers the temperature at which soot burns and turns to ash. And assuming the regeneration is successful, the soot is expelled from the exhaust as very fine ash during normal driving, and the whole process repeats itself each time the ECU determines that the DPF's pressure differentials indicate that it needs to regenerate.

So the first line of defence against any potential horrors is regular and prompt servicing and this is something I personally could not emphasise enough - especially if you are capable and competent enough to service your car yourself. Certainly in Ford's case, the engine uses a fully synthetic low ash oil that conforms to a particular standard. I always recommend buying the correct stuff from Ford because it's reasonably priced (under €30 for 5L) and is fit for purpose. I've used another brand that claimed to meet the Ford specification, but I noticed things with it which I wasn't happy with and stuck with the genuine stuff instead. Another benefit of this is that if you keep your receipts from Ford, it actually counts as a form of service history and proof of regular servicing which should pay dividends when it comes to selling the car on.

The indicated service schedule is 12,500 miles / 12 months for oil and filter replacement. Our car does ~ 16,000 miles per year, and I change the oil and filter every 6 months. The obvious logic here is that reducing the service life of the oil and filter reduces the risk of the oil sludging and build up of carbon generally inside the engine.

Here's a pic I posted a while back of a heavily sludged filter (left) from a DV6 in a Mazda 3 where the turbo died, and from the right, our C-max.




Another potential weakness - that is design related - is the way sump is fabricated. The drain bung is recessed upwards into the sump and the effect of this will prevent the sump from draining completely. Any heavy suspended solids in the oil could remain in the sump rather than draining out with the last of the oil. Ideally, the drain bung should be at the lowest point. One trick which could give a some relief here would be to drain the oil as normal, and then pour say half a litre of oil into the filler and allow it flow down through the engine and out the bottom. This in effect is using the fresh oil as a "mini flush" of sorts.



Ford issued a technical service bulletin some time back about the oil circulation issues and one item they recommended was removing the sump and cleaning the oil pump strainer. The sump will require replacement if it's removed because it goes out of shape when it is originally torqued up and won't seal properly if reused.


Another thing which I did some time back was to replace the oil feed pipe and banjo bolt / microfilter supplying the turbo. These are also known to clog and starve the turbo of oil. It's a silent failure as there's no warning it has happened until the turbo fails. Another potential design issue here is that the oil feed pipes come from quite high off the block. Temperatures here a higher than lower down, plus if there are any oil feed / oil pressure problems, these will manifest themselves more quickly the higher up the engine one goes.




In the pic below, the impeller is in perfect condition. In a defective turbo, the tips of the impeller tips will be bent back as the impeller shaft bearing will fail and allow the tips to come in contact with the turbo's casing. This will be aurally evident if it has happened...



So the upshot of this is to restate my earlier advice: regular servicing - ahead of schedule if possible -using the correct oil. I've also played it safe by replacing the turbo oil feed pipes. This proactive maintenance regime wont just protect the car, but the documented proof of regular purchases of the correct oil and filters will be a major plus when it comes to selling the car, and would give its new owner the confidence of knowing that they are buying a car that has been well minded and looked after.