Volvo airbag, introduced 1987
QUESTION: My Corvette is 20 years old and, while I can and do monitor and replace items as they age, one of the things I can't find out anything about is airbags.
How long do airbags last? Is there a replacement schedule? My local dealer says no, that they are good for the life of the car. That's fine, but what is the expected life of a car - the average life? How long is that?
Jeremy
Answer: Generally speaking when manufacturers talk about the average or expected life of a vehicle, they are referring to mileage, although in some cases it can be years.
On average, the industry figures consumers drive about 33,000 km a year and figure a lifetime to be in the range of eight to 10 years or in the 275,000 - 300,000 km range. Obviously, your Vette is outside either of those.
But the airbag is a sealed unit, not exposed to the elements or wear and tear or other factors that would affect the life of other components.
It is generally believed within the industry that airbags are good for 10-15 years without concern.
The various sensors and mechanisms that sense a crash and trigger an airbag deployment are solid state electronics controlled by a monitoring system that checks their efficacy every time you turn on the ignition. If there was a problem with the propellant or electronics, you would see a warning light.
But there is no way of looking into that sealed bag containing the bag itself. Most manufacturers recommend having them serviced or checked after eight to 10 years, but since they are sealed, there is very little that can be done beyond replacing them.
Replacement bags, when and if available, cost more than $1,000, sometimes far in excess, making that an expensive proposition.
If it were me, I'd continue to use the belts - which are the primary source of protection in a crash - and bet the bags will work for a few years yet.
Smoky exhaust
QUESTION: When I first run my car, a 2008 Chrysler Sebring with 38,000 km, in the morning there is a cloud coming out of the exhaust. It works fine, the oil level is always good when I check it. Where is the smoke coming from?
Walt
Answer: I suspect it is steam or water vapour, not smoke.
When the hot exhaust gases leaving the engine pass through the cold exhaust pipe, the result is condensation. You might also notice a few drops of water dripping off the end of the pipe or out of a small hole provided for just that purpose at a low point of the exhaust system. If the vapour clears or disappears quickly after leaving the exhaust, that is what you are seeing.
If in fact it is smoke, and dark or black, the problem is an over-rich mixture. The engine is normally fed about one part of fuel for every 15 or so parts of air, slightly more for a cold start. But if that ratio becomes too rich, i.e. there is too much fuel, the excess is evident as black or dark smoke out the tailpipe. The problem is the engine control computer and it should be checked.
The smoke is not your only reminder, your fuel mileage would suffer tremendously.
If the smoke is bluish in colour, the problem might be oil getting past the rings or valves and into the combustion chamber where it is burned as part of the combustion process.
If this were the case, you would notice a measurable amount of oil consumption and likely other issues as the oil could foul plugs or sensors.
Finally, a steady stream of thick white smoke that does not dissipate quickly may be the most serious of all, likely caused by coolant getting into the combustion chamber. Stop and call a tow truck immediately as this can quickly lead to total engine failure and thousands of dollars in repairs.