Expert answer

Hi Frank,

It's the timing belt itself that you've heard about most likely as, on some versions of the 1.0-litre Ford EcoBoost engine, it is what's called a “wet belt”. That means the timing belt actually runs in oil, where most timing belts do not.

Ford isn't alone in having problems with them. The rubber in the belts can degrade due to many issues including use of the wrong engine oil and impurities in the oil as it gets older.

The good news for you is that, while earlier examples of the 1.0-litre EcoBoost engine did use this setup (though not all), and Ford dropped it from 2022 on, the MHEV engines always used timing chains instead and they should therefore be more robust.

However, even those later engines use a rubber belt to drive the oil pump and that still runs in oil so potentially has all the same issues. It is too new for those problems to have come to light and Ford believes it is designed for the life of the engine because it is under far less stress than the timing belt was.

All we can advise is that you carry out oil changes a little sooner than recommended and that you always use the correct specification of oil.

Expert answer

Hi Aubril,

The Focus estate in general is pretty decent, but the 1.8-litre diesel engine was not Ford's finest hour and unless it has verified low mileage and/or a detailed service history showing regular oil changes, it's best to look for an alternative. The 1.6-litre diesel is a far superior engine from Ford, for example.

Expert answer

Hi Patrick,

That is very high mileage of course, but many diesels are quite capable of it so long as they're maintained properly. Look for a detailed service history covering oil changes in particular, and on-time timing belt changes as well. 

Even so, there's no doubt that a car with that mileage on it will require mechanical maintenance. I'd only consider such a car if the price was exceptionally low in comparison to other examples with lower mileages. 

Expert answer

Hi Colette,

Unless you're covering huge mileage, that seems way too often to us. If a Honda dealer has told you that, you should ask for clarification as to why, as, other than high-mileage, it would be normal for a new car such as that to have an oil change once a year - or when the built-in service indicator suggests it's needed.

Expert answer

Hi Jonathan,

Timing chains are designed for the life of the engine, so they do not come with a scheduled change interval. Make sure the oil changes are regular to keep the chain in good condition. 

Expert answer

Hi Kevin,

There is rarely ever such a thing as a scheduled timing chain replacement - they're designed to last the life of the engine. So long as you stick to recommended oil change schedules then we wouldn't expect the ix35's chain to stretch or wear excessively.

Expert answer

Hi Jeff,

That car has a timing chain so should need no maintenance other than timely oil changes.

Expert answer

Hi Rob,

They're a pretty solid car actually. Check the service history carefully and make sure that the 1.6 HDi engine has had regular oil changes with high grade oil. Black smoke means either a blown turbo or at least turbo seals and check the air conditioning to make sure it's chilling the air properly. 

Expert answer

Hi Gerry,

It's very difficult to assess such things from afar I'm afraid. It could be any number of things. Basically it comes down to spark, fuel and air, but of course, electronics also come into it, so a sensor could be faulty as well. The best bet is to bring the car to a good local mechanic to have a look.

Hope you get it sorted soon.

Expert answer

Hi F D,

There does seem to be an issue with the turbo- and supercharged engines involving the timing chain and it seems to be because Volkswagen tried to stretch the service intervals too far. Now, your A3 may not have that particular engine, depending on the year and the engine power. The lower power 122hp version of the 1.4 TSI didn't have a supercharger, just a turbo so is simpler and doesn't seem to suffer the same issues. The more recent 150hp version also does without the supercharger, so the best thing to do is not panic - if you're concerned about the car, take it to your dealer, have it inspected and maybe insist on a more frequent oil change.