Car Buyers' Guide: Why some engine issues crop up

Jack Biddle
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Changes to engine technology can be a headache at service time. Photo / Getty Images/iStockphoto

Changes to engine technology can be a headache at service time. Photo / Getty Images/iStockphoto

Engine issues crop up as makers move to new technologies

Daryn read a recent article in Driven "Economy above quality" which quoted an annual survey on vehicle dependability, highlighting the average number of problems per vehicle had increased for the first time since 1998.

Californian ratings and consulting company J.D. Power said its survey showed engine issues accounted for most of the increase in problems reported by owners of cars from the 2011 model year.

New engine technology to save fuel - including direct injection, turbocharging, automatic stop/start systems and transmissions with higher gears - were all highlighted in the survey with an increase in engine hesitation, rough transmission shifts and lack of power.

Daryn asks if those trends are likely to be followed here.

Well, we have already seen many new technologies and unwanted mechanical issues arrive here via used imports, particularly in the early days.

Engines that were designed to meet emission standards in countries such as Japan arrived in large numbers and soon started to develop a number of rough running issues.

From outside appearances, many of the well-known and popular makes/models looked the same as what was sold new here, but it soon became clear that it was dangerous for mechanics to assume engine, transmission or even suspensions were identical.

Many of the "fixes" were simply a best guess by garages including the franchise holders, and if all else failed emission gear was either blocked off or disconnected and catalytic converter removal was not uncommon.

Having fuel with high sulphur content in those early days did not help matters either. Early versions of lean-burn engine technology which have used direct injection and/or high compression engines, have had their problems with a heavy carbon build-up in the manifold inlet tracks and rough running not uncommon and fairly expensive to repair.

Some manufacturers have used other engine designs to achieve low fuel consumption and tail-pipe emissions but at times the customer still has a few unpleasant surprises waiting at time of service.

We also saw the mass introduction of Constant Variable Transmissions (CVT) via used imports. The early efforts to reduce fuel consumption using this technology were littered with mechanical issues.

But CVT technology has moved on from those early days and is being used by more and more manufacturers today.

Some of the European brands that went for the Direct Shift Gearbox (DSG) as an alternative to the conventional automatic have also had some issues to overcome during production.

I have often thought manufacturers of starter motors are never going to go out of business anytime soon with the introduction of start/stop technology, especially when vehicles age and are driven in built-up areas on a regular basis.

Hybrids use their electric motor to restart so they are immune from any future starter motor issues.

I suspect the results of the J.D. Power survey are not a total surprise to the individual manufacturers and design teams.

Customer dissatisfaction is not only reflected in negative publicity but hits them financially with unwanted warranty and out of warranty customer good-will costs.

While the industry can act very quickly to overcome unwanted problems, it must be remembered while improvements are introduced during a vehicle's lifespan, the production lines don't stop so there will always be updates or recalls to attend for those vehicles already out in the field with known issues.

A high number of owners will retain their loyalty to a brand if problems are solved quickly and if necessary at no cost.

If you buy an older used vehicle then it pays to try to find out all the negative points and it's dangerous to assume there is a particular brand that is fault free and bulletproof.

If you're in the market for a new vehicle, then you can almost guarantee there will be upgrades and improvements made as a result of customer feedback during production.

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