Q. I recently replaced the water pump in my Nissan Quest. The problem now is I don’t have consistent heat. I have tried to bleed off any air but still have the same problem. The heat worked fine before I replaced the water pump. What did I do wrong?

A. The problem could still be air in the system. I have seen some elaborate procedures to bleed off an air blockage. Some Nissan vehicles require the car to be jacked up nearly two feet to remove any trapped air. Don’t overlook the obvious and read the shop manual to see if there is a specific cooling system bleeding procedure.

Q. I changed a burned out bulb in my car, but the new bulb doesn’t work. I took it to my local repair shop, and they needed to scan and reset the computer to get the bulb to work. What is happening to cars that I need a computer to replace a headlight bulb? Is this a plan by auto manufacturers to block car owners from doing their own repairs?

A. In many cars almost all the electrical functions run through a body control computer. If the computer detects a fault in the code, that code needs to be cleared before the new part will work. In some cases, this can be performed by disconnecting the battery and erasing all the computers memory. This complication is an issue that is not just affecting the DIY’er but the professional technician as well. Many technicians today need to purchase the factory scan tools and data (if available) rather than a more generic version to fix even what was once a simple problem. Years ago it was almost impossible to get factory information from the vehicle manufacturers; today, with a push from the repair industry for Right to Repair legislation, I believe we are seeing more information available than ever.

Q. I have a Volkswagen Jetta, and the mechanic told me the car needs a catalytic converter. The car runs okay, but the check engine light is on. Would the catalytic converter make the car run poorly or use more gas?

A. In some cases when a catalytic converter starts to fail, it will trigger a check engine light indicating a lack of efficiency. In other cases, the engine will be sluggish and could use more gasoline. Depending on the replacement part, the repair cost could range from $800-$1500 dollars.

Q. Do you think there is a future in the auto repair business? My son is in high school and is considering a career in fixing cars. What do you think?

A. There are roughly 250 million passenger vehicles registered in the United States, and someone needs to keep them running. Even though the recent news of dealerships closing doesn’t sound optimistic, these 250 million vehicles will need to be repaired and maintained. The U.S. Bureau of Labor expects a 14 percent job growth over the next 10 years. This could also be due to the growing population, as well as the number of older technicians that are retiring. In my opinion offers, there is a good future for a young technician, especially one with post secondary school training. Add in good problem solving skills and computer experience, as well as customer service skills, and I believe the future of this business looks very good. Many technicians today make between $12 and $25 per hour with some dealerships telling me their most talented technicians are making $100,000 a year.

Q. On the recent cold mornings, when I turn my heater on, the windshield fogs up. I took the car (1999 Ford Taurus) to a local repair shop, and they told me the heater will need to be replaced. They told me the cost would be $600 to $700 dollars. Is that possible? Right now I’m not using the heat, but it is getting cold.

A. The heater core is the cheap part costing $60-$70; it is the labor that makes the job expensive. To replace the heater core will take 5-6 hours of labor, add in coolant, replacement of any old heater hoses and clamps, and it is easy to see how the cost can add up to $700 or more.