2023 Mazda CX-5 Pricing and Specs

The problem of the sump filling with diesel was not unknown on early CX-5 diesels. A leaking injector is possible, but the main cause of this was believed to be the car’s DPF regeneration process dumping large amounts of fuel into the engine, some of which finds its way past the piston rings and into the sump. Either way, a new engine is a large expense.

There’s every chance that Mazda won’t offer any help given the age of the vehicle, nor is this type of engine damage usually a cause for an insurance claim. It would definitely be worth contacting Mazda Australia’s customer service division, but don’t hold your breath.

Proper maintenance is overlooked by many car owners, and it’s a real problem. Modern engines work very hard and have lots of intricate oilways and mechanical clearances that simply won’t tolerate dirty oil. On paper, the car you’re looking at hasn’t had clean oil or a filter change in 20,000km and that’s an awfully long time between drinks. In fact, it’s enough to perhaps give Mazda cause to void any new-car warranty remaining on it, should something mechanical go wrong.

Your best option would be to find another CX-5 with the options and in the colour you want, but with an up to date and complete service record. That’s the best way to prevent any major disasters down the track. The good news is the CX-5 was a popular model, so there should be lots to choose from.

A second-hand engine from a wreck is often a good an option, but only if you can find one that has been tested and comes with a warranty, otherwise you could be replacing your worn engine with an even more worn one. But with a diagnosis estimate of $5000 (and any actual repairs on top of that) I reckon a different workshop would be your best option. Frankly that seems (on the surface) a ridiculous figure and suggests that the workshop in question either doesn’t want your business or is assuming you’re a sucker.

Low oil pressure can be caused by various problems, and a good workshop should be able to check it out and give you a definitive answer on whether it could be fixed or the whole engine replaced. The good news is that the CX-5 is a popular model, so a replacement engine shouldn’t be too hard to track down.