Why your car may fail to start

Vehicles held up in a gridlock. Although it is advisable to switch off the engine whenever you are held up in a traffic jam, some vehicles may fail to restart due to some problems. However, you should nmaintain a good distance between your car and the one ahead of you. PHOTO BY ISMAIL KEZAALA.

What you need to know:

There are some embarrassing situations when your car stalls in the middle of a busy road. Incessant hooting and shouting from other impatient motorists may even make you panic the more. This sometimes happens when you briefly switch off your engine in a traffic jam. However, there are ways to avoid such situations.

A few weeks ago, I was walking on Kampala Road, when, I saw a gentleman pushing his friend’s vehicle which I suspected had a mechanical problem. When I moved closer to ask, the driver told me, “I had just switched off the engine to save fuel because I was in the middle of a traffic jam but it had no problem,” he said. It wasn’t long before I saw another person experiencing the same problem on Jinja Road, so, I set out to find out what the two cars’ problems could have been.

Switching off is healthy
It might have happened to you, or you are among those who are yet to experience it but have thought about how embarrassing or even frustrating it can be. I could tell from these drivers I saw. They looked uncomfortable.

“For the average rush hour traffic hold ups, that is to say 20-30 minutes or more, switching off your engine can save 10 per cent of your fuel. And for the lovers of the eco-system, if motorists can a adopt the culture of switching off engines instead of idling in traffic jams, the amount of reduced carbon dioxide pollution of the environment would be great and this would slow down environmental degradation,” says Paul Kaganzi, a mechanic.

Wear and tear
It is also true, as Kaganzi puts it that: “switching off an engine when held up in a traffic jam slows down the unnecessary wear and tare of moving engine parts like the water pump and the cooling system or the alternator in the electrical system.” That aside, the concern is on trying to restart the car and it fails. Think about that moment when the traffic lights turn green and the vehicle refuses to respond.

Kaganzi says: “Even after a short switch off, the vehicle can fail to start.” He says while it is rare, it can happen when there is a breakdown of the in-tank fuel pump, which is usually due to failure to replace the fuel filter eventually clogging and damaging it (fuel filter),” he says. He adds: “Keeping your fuel gauge at the empty or red mark most of the time can damage the filter. The fuel pump is cooled and lubricated by fuel in the tank, therefore it runs dry and gets damaged when the tank is almost empty,” he explains. For those who have experienced it, it is a very unwelcome situation and sometimes creates anxiety when surrounded by other vehicles.

“It is very embarrassing, it happened to me at the Wandegeya traffic lights. Other drivers were hooting and my vehicle could not start,” says Jamil Kintu, a taxi driver in Nakawa. “I fidgeted with the ignition but the car couldn’t start again, I asked people around to push me aside. I later realised the car had a problem in the ignition,” he explains.

Why it happens
Kaganzi says ignition coils or cables in older engines can prevent a car from restarting. “When the ignition coils, cables or spark plugs are damaged, they produce a weak spark which causes poor performance and may cause a hard start or outright failure to start the car,” he says adding: A dirty air cleaner element, worn out spark plugs, a clogged fuel filter and soot filled throttle chamber can cause poor performance, a hard start or outright failure to start.”

According to Robert Kalema, a mechanic along Jinja Road, failure of a car to restart indicates a problem. “It is either a problem in the wiring system or the battery,” Kalema argues.

“In most cases there is a wiring problem in a vehicle that fails to start after a brief switch off,” and he advises that: “Look at the wires coming from the positive battery terminals and the wires going to the radiator fans. If these wires are corroded and insulation is missing, you need to replace these harnesses.”

What to do
“The best thing to do to is keep calm and ask people around to help you push the car aside so that you can park safely,” says Ronald Magezi, a mechanic in Nakawa. He adds that “once you notice a problem with the starting system, do not fumble because during such a time, drivers become anxious and can easily cause an accident,” Magezi says.

Kaganzi also adds that sometimes the vehicle might have a faulty sensor or electrical component which can prevent restarting. “There are several sensors which help the Engine Control Module (ECM) determine when and how much fuel to deliver to the engine combustion system,” he says.

Kaganzi adds, “Sensors monitor the crankshaft and camshaft position, air intake temperature and volume as well as the engine temperature and exhaust smoke condition.” The mechanic adds that this helps the ECM regulate fuel delivery. “When any of the sensors fails, it will deliver wrong fuel amounts (too little or too much) which will cause difficult starting or failure to start,” Kaganzi explains.

Keep a distance
Despite most causes being mainly mechanical, sometimes the vehicle might be in a perfect mechanical condition but some drivers experience the problem. “When you are driving in a place like Kampala, you are actually
not driving one car,” Kintu observes.

“You have to calculate the distance between the cars around you and the car you are driving,” Kintu says adding that this is not easy especially for new drivers.

“New drivers get scared when the car does not start immediately,” he says. “Sometimes the car requires pressing on the brake pedal and clutch pedal or sometimes both while then turning the key to restart the car. This is a feature with some newer cars intended to prevent them from taking off unpredictably when they are turned on,” Kintu notes. This means that the clutch pedal must be pressed for the car to start,” he adds.