When this occurs, the best thing to do is limit your driving and have the problem diagnosed by a mechanic as soon as possible, according to CarMD, which collects repair data on 136 million vehicles based on “check engine” incidents.
Virtually all vehicles manufactured since 1996 are equipped with a “check engine” light, which is part of an on board diagnostics system that is constantly checking information from engine to transmission sensors to look for emissions-related problems. It’s found on more than 220 million vehicles in North America, and covers about 80% of the systems on most cars, light trucks, SUVs and minivans.
The most common failure is the oxygen sensor, which monitors the amount of unburned oxygen in the exhaust and tells your car’s computer when there is either too much, or not enough fuel. Getting it replaced costs less than $200. Ignore it and you’ll likely see a 40 percent drop in your car’s gas mileage. The same goes for the mass air flow sensor, which calculates the amount of air coming into the car and determining yhow much fuel to shoot into the engine. If it goes bad, your mileage could drop by up to 25 percent. It costs about $375 to fix, but will save you money at the pump.
Getting the “check engine” light to turn off could be as easy as replacing a spark plug. Spark plugs are responsible for igniting a car’s air/fuel ratio. When they fail, they can cause an engine “misfire,” reduce your gas mileage, and ultimately ruin your car’s catalytic converter. If you do it yourself, replacing a spark plug can cost under $10. Having it done by certified mechanic costs a couple hundred dollars, but can save you thousands. A damaged catalytic converter will cost $1,000 or more to fix, but is avoidable if you address small problems early.
CarMD looked at real-life repair data for one full calendar year on 2002-2012 vehicles and discovered that different brands tend to have a unique set of problems and common failures. For instance, a malfunctioning oxygen sensor accounted for about 28 percent of Mini repairs in 2012, while bad ignition control modules accounted for 26 percent of Saab repairs, according to CarMD. Subaru had a tendency to need a new catalytic converter (22%); and Scion was susceptible to loose or damaged gas caps (20%).
The CarMD Vehicle Health Index points out common problems by brand, which may be important to know as you consider future maintenance costs.
Audi A6Audi vacuum hosesRepair cost: $95
When the "check engine" light goes on in an Audi, there's a good chance it's because of a faulty vacuum hose. CarMD says about 13 percent of all problems reported with Audis were solved by inspecting and repairing faulty vacuum hoses.
BMW vacuum leaks
Repair cost: under $100
BMW engine warning lights are often traced to vacuum leaks, according to CarMD. They're to blame in about 14 percent of cases when the "check engine" light goes on.
Chrysler gas caps
Repair cost: $208
If the "check engine" light in your Chrysler vehicle goes on, you might get lucky. About 10 percent of the time, the problem is only a loose gas cap, which can be fixed for free. But just as frequently, you could have a clogged exhaust gas recirculation valve in the emissions system.
Hyundai oxygen sensors
Repair cost: $221
The most common "check engine" light repair in a Hyundai is the replacement of the oxygen sensor. In fact, CarMD says that's the most common repair on all vehicles in the U.S. Not getting it repaired can hurt your gas mileage by as much as 40 percent.
Jaguar XFJaguar ignition coilRepair cost: $483
When Jaguars end up in the shop for a "check engine" problem, most often it's to replace the ignition coil and spark plugs, at an average cost of $483 for parts and labor.
Jeep oxygen sensors
Repair cost: $185
If the "check engine" light in a Jeep signals trouble, it could be a faulty oxygen sensor. CarMD says 13 percent of Jeep repairs involve the oxygen sensor, which monitors the mix of oxygen and fuel in the exhaust system.
Land Rover spark plugs
Repair cost: $752
Trouble with Land Rover SUVs is most often traced to the spark plug wires and spark plugs, which are the culprit in about 15 percent of "check engine" incidents. Replacing them can cost a hefty $752 for parts and labor.
Lexus oxygen sensors
Repair cost: $300
When the 'check engine' light comes on in a Lexus, it's usually a common problem: the oxygen sensor needs replacing. It'll cost about $300 to replace, and well worth it to optimize fuel economy.
Lincoln ignition coils
Repair cost: $376
The most common 'check engine' repair in a Lincoln is replacement of the ignition coil and spark plugs. That's the culprit in 14 percent of diagnostic checks.
Mazda CX-5Mazda catalytic converterRepair cost: $938
If the 'check engine' light comes on in your Mazda, you'd better hope it's not the catalytic converter. CarMD says that's the most common culprit (13 percent of repairs) in all Mazdas. And it's not cheap, averaging $938.
Mercedes-Benz mass air flow sensors
Repair cost: $521
The most common repair in a Mercedes when the 'check engine' warning comes on is replacement of the mass air flow sensor. It works on conjunction with the oxygen sensor to ensure the right air/fuel mix in the engine.
Mini oxygen sensors
Repair cost: $353
More than 25 percent of the MINIs brought in for service after a 'check engine' warning occurs need to have the oxygen sensor replaced.
Mitsubishi oxygen sensors
Repair cost: $343
Mitsubishi cars are prone to problems with oxygen sensors too. Diagnostic tests confirm the O2 sensor is to blame in about 20 percent of 'check engine' warnings.
Nissan AltimaNissan catalytic convertersRepair cost: $840
The catalytic converter needs to be replaced in 15 percent of Nissans that experience a 'check engine' warning. That's a pricey repair, averaging $840.
Porsche mass air flow sensors
Repair cost: $704
Diagnostic tests most often point to trouble with the mass air flow sensor in a Porsche. It's to blame in about 12 percent of the cases involving a 'check engine' warning.
Saab ignition control modules
Repair cost: $435
Although Saab is defunct, there are plenty of older models still on the road. The most common source of trouble when the engine warning light comes on is the ignition control module. CarMD says it's to blame in 26 percent of the cases it reviewed.
Scion gas caps
Repair cost: $149
If the 'check engine' light comes on in your Scion, don't freak out. About 20 percent of the time, it's nothing more than a loose gas cap. Even if it's the evaporative emissions vacuum switching valve, the next most common problem (17% frequency), the repair isn't too costly.
Subaru ImprezaSubaru catalytic convertersRepair cost: $935
Subarus tend to be very reliable, but when they do end up in the shop with a 'check engine' warning, 22 percent of the time it's because the catalytic converter needs to be replaced.
Suzuki oxygen sensors
Repair cost: $385
Faulty oxygen sensors are the most common repair on Suzukis, accounting for 24 percent of the 'check engine' incidents. But just as often, it could be a loose gas cap, so get it checked out.
Toyota catalytic converters
Repair cost: $1259
When the 'check engine' warning comes on in a Toyota, diagnostic tests point most often to the catalytic converter or the oxygen sensor, which together account for about 25 percent of the problems. The O2 sensor is about $279 to replace, but the catalytic converter is much more expensive - about $1,259 on average.
LINK
Posts
