What the dealer is saying (most likely) is that the fuel pump will be fixed under warranty but there’s a question mark over the condition of the intercooler. They’re probably separate issues. If the intercooler has failed because of faulty materials or manufacture, then it would be covered by the warranty. If it’s been damaged (a flying rock, perhaps) then it won’t be covered by warranty. At which point, you’re liable for the cost of repairs and diagnosis.

The question you need to be asking is why the dealer thinks the intercooler needs to be tested. Is there anything leaking from it? Are there any performance problems pointing to the intercooler being damaged? If not, it’s hard to imagine why the intercooler would need to be tested in the first place, apart from the manufacturer warning dealers of potential failures. Which, again, would point to a warranty issue.

Don’t be afraid to ask the tough question before any work has commenced, and don’t forget that your state motoring club is a good source of legal advice on this stuff.

But you should also know that this model was involved in a safety recall to address a problem with the cooling system where a failure of the plumbing could allow coolant to escape. If this is part of your problem, it would very likely be considered a warranty job.

Let’s start with the concept of a dealership charging for a problem that is probably a warranty claim in the first place. Warranty repairs shouldn’t cost the owner anything, so the dealership is skating on thin ice in the first place.

But secondly, this doesn’t sound like a problem at all. In fact, I’d say it’s perfectly normal behaviour. What’s happening is that the car’s computer is looking at how much fuel the vehicle has used in the immediate past, and calculating how far you can go on the fuel you have left, at that rate of consumption. When you switch from stop-start running to highway driving, your consumption per 100km falls. When the computer notices this, it recalculates how far you can go with your reduced consumption, and the estimated range on the trip-computer goes up.

Fuel range is the inverse of fuel consumption, when consumption goes down, range goes up. And since the car’s computer models the range based on your recent consumption rate, highway running will usually cause the range to creep up. Eventually the range will plateau and then begin to fall. When you hit the city, the range will begin to fall more quickly. The dealership should have been able to explain this to you rather than threatening to charge for taking a look at it.