Methods for Clearing Out Engine Carbon Buildup

Dear Doctor: I have a 2009 Mini Cooper S with 72,000 miles. The check engine light says “engine malfunction.” Under a high load, a high engine load will result in damage to the catalytic converter. It sounds like I may need to have carbon buildup cleaned off the intake ports, and the back side of the intake valves. Does the 2009 model year Mini Cooper have direct injection? Is there any type of additive I can try first? Charles

Dear Charles: The first step is to find an actual fault code in the computer’s memory. The technician will look at when the fault happened in freeze-frame memory, and review all of the engine data and compare the actual sensor information to the factory specifications. Carbon buildup is very common. The monthly use of a quality fuel additive, such as Seafoam or Techron, along with filling the tank with premium gasoline can make a big difference. Also, quick acceleration getting onto the highway also helps clean off carbon deposits. Catalytic converter damage will usually occur when the engine misfires (flashing engine light indicator). Another catalytic converter concern is an engine that runs lean or rich, which causes the converter to overheat.

Dear Doctor: I frequently drive at night and noticed that the oncoming traffic headlights are extremely bright and at times hinder my sight, including in my rearview mirror as well. Is there a government standard on light requirements or is it up to the automobile manufacturer? John

Dear John: There are government light standards regulated by the Department of Transportation. Headlight technology has changed over the years — and yes, newer headlights are bright and very white in color, such as the LED headlamps. There still some projection style halogen headlights used by some carmakers. And some vehicles have active headlights that swivel and move as the steering wheel is turned. It seems as we age, our eyes become more sensitive and vision is affected by headlights.



Dear Doctor: My 2004 Honda CR-V has 132,000 miles. I hear a shuddering sound in the transmission at 30 mph. The dealer took it on a road test and confirmed the sound, so they checked the transmission fluid level and they also checked for fault codes. It came back with no codes and the fluid was full and clean. They suggested a transmission replacement with a factory Honda unit at a cost of $3,800, plus mounts, drive axles, and any other worn parts. The transmission shifts fine. What would you do? Mike

Dear Mike: The most common fault is the torque converter not allowing enough slippage. Some vehicles require a computer software re-programming to resolve the problem, while others can benefit from a transmission fluid change. If the filter is serviceable, then replace it and use the correct fluid, plus a bottle of friction modifier. The transmission additive will actually lessen the friction properties of the fluid. In some cases this will stop the shudder. Another option is to push the small button on the shifter, if equipped. This will prevent the torque converter from locking up, thus eliminating the shudder.

Dear Doctor: I relocated from Florida to New York. I’m told that my 2015 Dodge Challenger is not good to drive in the snow. It’s a rear-wheel-drive car with the Hemi engine. What do I need for winter driving in this car? Susan
Dear Susan: Rear-wheel-drive cars are not the best suited for inclement winter driving. The Hemi Challenger is a fun car to drive, except in the snow, and snow tires will make a big difference in winter driving. You’ll need to buy four tires; you can buy a tire-and-wheel package all mounted, and they even come with tire pressure monitors. When driving in the snow, go easy on the brake when stopping and easy on the gas pedal when accelerating.

Dear Doctor: Have you test-driven the new 2018 Hyundai Sonata Sport sedan? Jan

Dear Jan: Hyundai never ceases to amaze me with its vehicles. I drove the Sonata Sport sedan powered by a 2.4-liter direct injection four-cylinder rated at 185 horsepower paired with a sport-mode paddle shifting six-speed automatic transmission. Priced at $26,210, the Sonata Sport drives and handles like a more expensive vehicle. The transmission is smooth, as is the suspension, which softens all the road imperfections, while body insulation eliminates tire road noise from course asphalt. EPA is 25 mpg city, 35 mpg highway.

— Junior Damato, Motor Matters

Copyright, Motor Matters, 2018

(Manufacturer photo: 2009 Mini Cooper)

Junior Damato is an ASE-certified Master Technician.

E-mail questions for publication to [email protected]

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