: 2684x2334 px
: June 12, 2018
An old oxygen sensor (say, 90,000 miles or more) may still work well enough that it doesn’t trigger the check engine light but could still hurt fuel economy. Engine performance can also be reduced by more serious internal problems, such as valves that don’t seat properly or worn piston rings, or by restrictions in the exhaust system. Because the same symptoms can suggest different problems, and there are often several possible causes and cures, it’s better to consult a professional mechanic than to try to be one if you have neither the experience nor the right equipment to diagnose drivability problems. In short, rather than ask for a tune-up, tell a mechanic what you’re experiencing and ask him or her to find the cause.
Alternator: now this was a breakthrough!! Before the alternator was the dynamo-machine. A DC generator who wasn't that bad, but had a lot of glitches, the regulator system was complicated, it was large and in some cars highly unreliable. Then came the alternator. It was brilliantly constructed, highly dependable, half the size of the dynamo and very easy to repair. The output that it gave was much more stable and consistent thus allowing more appliances to be put in the car.