Injectors Mazda: problems by model and engine

Documented faults, from most to least important

Severity × frequency. Below each one, the Mazda models it appears in.

- High severityFrequency: CommonMZR-CDOil dilution from leaking injector seals and DPF regenerationsOn the 2.0 and 2.2 MZR-CD, injector seals that age badly and incomplete particulate filter regenerations on short journeys can let unburnt diesel into the sump, diluting the oil and leaving the engine with less lubrication.
In 3 I, 3 II, 5 I, 6 I, 6 II and CX-7
- Medium severityFrequency: Very frequent1.4 HDiInjectors that lose their seal and let diesel escapeThe most cited weak point of the 1.4 HDi is its injectors: over time they can lose their seal and let diesel escape, which is usually noticed as a smell of diesel in the car. It appears in the two most common outputs (68 and 70 hp) and in both cases it is identified as the engine's main weakness.
In 2 I
- Medium severityFrequency: CommonSkyactiv-DCarbon build-up in the intake, EGR and injectorsUrban use and short journeys encourage carbon build-up in the intake manifold, EGR valve and injectors of the Skyactiv-D, with loss of power and uneven running; it is documented on the CX-5, the Mazda6, the Mazda3, the CX-3 and the CX-30.
In 3 III, 3 IV, 6 III, CX-3, CX-5 I and CX-5 II and 1 more model
- Medium severityFrequency: CommonMZR-CDCarbon on the injectors, EGR valve and intakeUrban use and short journeys encourage carbon to build up on the injectors, EGR valve and intake of the MZR-CD, with loss of power and jerking; documented on the Mazda6 and Mazda3, on both the 2.0 and the 2.2.
In 3 I, 3 II, 5 I, 6 I, 6 II and CX-7
- Medium severityFrequency: Common1.6 HDiLeaks at the injector washers and carbon build-up in the cylinder headIt is common for the copper washers of the 1.6 HDi injectors to stop sealing: the engine blows gases, carbon forms around the injector and soot gets into the oil. It is cheap to repair, but if left it contaminates the oil and is one of the causes of turbo failure.Repair (garage): €110–€310
In 3 I
- Low severityFrequency: CommonSkyactiv-GCarbon build-up in the intake manifold and injectorsLike almost any direct-injection petrol engine, the Skyactiv-G accumulates carbon on the intake valves over the miles and can foul the injectors, with loss of power and a rough idle; gebrauchtwagenberater.de documents it on the Mazda2, Mazda3, CX-3, CX-30 and CX-5.
In 2 II, 3 III, 3 IV, 6 III, CX-3 and CX-5 I and 3 more models

By Mazda model

Open yours to see only the faults that affect it, by engine and by year.

Engines and gearboxes involved

Parts for your Mazda for faults with the injectors

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Injector
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Frequently asked questions

What faults with the injectors do Mazda cars have?

In 16 models from Mazda there are 6 documented faults with the injectors. The most important: oil dilution from leaking injector seals and DPF regenerations, injectors that lose their seal and let diesel escape and carbon build-up in the intake, EGR and injectors. Each fault has its own page with the affected years and versions, the symptoms and the repair cost.

Which Mazda models have the most problems with the injectors?

Mazda 3 I (3 faults), Mazda 6 I (2 faults), Mazda 5 I (2 faults) and Mazda CX-7 (2 faults).

Which Mazda engines have faults with the injectors?

MZR-CD (2 faults), 1.4 HDi (1 fault), 1.6 HDi (1 fault), Skyactiv-D (1 fault) and Skyactiv-G (1 fault).