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you & your car

Why do all cars these days have tachometers? I can see why cars with a stick shift could have an instrument showing rpm (that is if the drivers cannot tell their engine speed by listening), but surely these instruments are irrelevant for cars with automatic transmissions – most cars in North America. – John

It's an affectation.

You are correct, there is no need for a tachometer in 99 per cent of today's vehicles.

It is useful with a manual transmission when driving a performance vehicle and when trying to wring maximum fuel mileage out of a engine. In both cases, knowledge of the points at which an engine produces maximum horsepower and torque can help a driver wring maximum performance or maximum fuel efficiency from the vehicle. But only a small minority of drivers know what it is and most of them use it to shift close to the red line.

Designers love to match it with a speedometer to balance the instrument package appearance or give the impression you are driving a "sporty" or performance vehicle.

Filling up

When I fill the gas tank of my Kia Soul I have to fight to get it full. The automatic shut-off thing keeps activating long before the tank is full. It does not matter what brand of gas or station or how full the tank is when I try to fill it up. Do you have any idea what is wrong?

The fuel tank vent is probably blocked or has a kink in it.

To prevent harmful emissions from escaping into the atmosphere, the tanks of modern vehicles are vented so the fumes from the fuel entering the tank are diverted through filters and check valves where they are captured.

The filler neck on most vehicles has to wend its way in a circuitous route from the side of the vehicle to the fuel tank. The vent hose, connected to the filler tube somewhere close to the opening, has an equally if not more tortuous route. Most of these vents are soft rubber-like material and can become kinked or blocked.

The gasoline pumps at the station have back-pressure sensors that detect when the fuel flow is slowing or stops – as would be the case when it is full, or if the vent is blocked. When this happens, the pump shuts off.

These automatic shut-off systems are set to very close tolerances to prevent fuel from spilling out the filler neck, down the side of your vehicle and into the atmosphere. The solution is to pump the fuel slowly until you can get to a dealer and have the vent hose checked. If it kinked or blocked, that is an emission issue and the repair should be covered by warranty.


I keep an old Ford Ranger at our summer place and use it there during those months. Near the end of summer, it would not start. I used a battery tester and determined the battery was dead. I bought a new one and took it up the last time we went there. Even with the new battery, it still would not start. Any ideas? It is a long way to the nearest service centre and it would have to be towed, which would be expensive. Any ideas?

You don't say whether or not the engine turns over with the new battery.

If it does, you need two more things to get the engine to start, compression and fuel. I assume you have both since you do not mention having problems starting before the dead battery.

The first thing I would do is check the connections. You can buy and use a small wire brush tool designed specifically for cleaning battery terminals and the inside of the cables. Make sure they are shiny and clean. Check both ends of the cable while checking them for condition.

One other thing that comes to mind is to check to see if all the accessories are turned off when the ignition is switched off and the key left in the ignition. That should be the case with your Ranger, although it is not with some German vehicles.

Since you have a new battery the problem is not likely to be the charging circuit and/or alternator. My best guess: one or more poor connections.