Renault 1.5 dCi and Ford 1.0 EcoBoost — two typical weak points

Renault 1.5 dCi: injectors, turbo and oil quality

The 1.5 dCi is one of the most-produced diesel engines in Europe; it sits in many Renaults and Dacias. Its strength is economy; the areas to watch are mainly these:

• Injectors. At higher mileages they atomise less precisely. Signs: rough idle, difficult cold starting, smoke and an engine that "rattles" at low revs. On replacement the injector codes must be entered into the control unit — otherwise the engine will not run as it should.
• Turbo and oil supply. The turbo depends on clean oil through a thin feed line. Extended oil intervals and lots of short trips let that clog; the result is turbo damage announced in advance by whistling, oil consumption or blue smoke.
• EGR and particulate filter as on virtually every modern diesel: lots of city driving stresses both.

The common thread on this engine is oil: to specification, on time, and preferably more often if the car mainly does short trips.

Ford 1.0 EcoBoost: cooling and timing drive

The 1.0 EcoBoost is a compact turbocharged three-cylinder delivering surprising power for its size. Two points deserve attention:

• The cooling system. On some versions there have been issues in the past with components of the cooling circuit. The risk on this compact, hard-working engine is that overheating quickly leads to serious damage. So take the temperature gauge seriously: with a red temperature light, stop immediately rather than "pushing on a bit". If coolant disappears with no puddle under the car, read coolant disappearing with no visible leak.
• The timing belt. Some versions have a belt running in the engine oil, with the same considerations as the PureTech: oil quality, interval and the risk of released material blocking the oil pump pickup. See timing belt in oil for the full explanation of that principle. Which version you have depends on model year and variant — we check that on the registration.

What both engines have in common

These are small engines working hard: turbo pressure, high specific loading and little material to absorb heat. That makes timely servicing weigh more heavily here than on a large, lightly loaded engine. Postponed maintenance costs a component sooner on this type than on an older, simpler design.

Practical advice

• Check the oil level monthly and before a long journey.
• Use oil of the correct specification; "roughly right" does not exist here.
• Let the engine idle briefly after a hard drive before switching off — that helps a turbo.
• Take coolant loss and temperature fluctuations seriously, certainly on the EcoBoost.
• Take a longer drive regularly if you mainly do short trips.

What we do

We read out the engine control unit, assess the oil and cooling system and measure where the values call for it: boost pressure, fuel trims, injector corrections. On a purchase or a car with unknown history we look specifically at the points belonging to that engine type — that is the difference between a general check and targeted diagnosis.

What comes after the diagnosis is repair work: engine and mechanical repair in Tilburg.

Independent garage — not an official dealer. Brand names and model designations are used solely to indicate which vehicles we carry out this work on.