Undercar

  • Cooling system service remains on the "bread and butter" list for many aftermarket repair shops. Modern cooling systems certainly don't have to be serviced nearly as often as they once did. Top-notch shops always are adjusting their practices in ligh
  • Adding or subtracting as little as one pound of pressure from a NASCAR tire can impact how the racecar handles on the track. And that can spell the difference between winning and losing in a competition that tries to even the playing field by regulat
  • Struts affect steering, braking, stability, ride quality and road feel ? and they actually help keep the wheels firmly against the road so the tires can do their jobs, too. But unlike, say, brake pads that have wear indicators or sensors to indicate
  • Ever hear of the government's Corporate Average Fuel Economy (CAFE) regulations? First enacted by Congress in 1975 in response to the oil embargo of the era, it sets fuel economy standards for passenger cars and light trucks sold in the United States
  • For many drivers, parking brakes are an afterthought — if they're thought of — and that's not good. This too-often overlooked system serves an important purpose. That purpose has nothing to do with emergencies; banish the term "emergency
  • When faced with a drivability complaint, I want testing methods that will provide as much information in the shortest amount of time possible. Using a pressure transducer and a good scope instead of a mechnaical compression gauge can do just that.
  • Hybrid vehicles are an excellent choice for anyone looking to save money at the gas pump while helping the environment. Yet worries about expensive upkeep, ranging from high voltage (HV) battery replacement to the fear of dealer-only repairs, weighs
  • GM vehicles have used electric power steering (EPS) systems for almost a decade now, so odds are good you've already worked on a vehicle using the system. Interestingly, it's not just expensive or luxury models that use EPS. Because the system is suc
  • The radio is playing loud enough to drown out the kids in the back seat, who themselves are engrossed in the SpongeBob SquarePants video playing on the DVD. The phone is ringing, adding another demand to our attention as we try to stay focused on the
  • The headline might give you the impression that the subject is all about testing coils, spark plugs and plug wires. But we are referring to analyzing the electron behavior in the combusion chamber. The objective is to look at the effect of fuel mixtu
  • What are the most common brake complaints that concern your customers today? According to Rob Backode, product manager for Bosch Automotive Aftermarket Brakes, they have found that they involve noise, unusual or premature wear and dusting. In additio
  • Some shops delegate routine brake service to their less experienced technicians, because, after all, it's just a brake job. But they don't know what they don't know, do they? While the shop might have opened up time for its more experienced techs to
  • Customers seem to want their little sedan to ride like a big luxury car, even if it has a few hundred thousand miles on the clock. But diagnosing ride quality issues isn't always easy, especially because most components on higher-mileage vehicles jus
  • Manual transmissions will be an important element in meeting future fuel economy and emissions standards, worldwide. In terms of efficiency, manual transmissions are nearly 97 percent efficient in transferring engine power from the engien to the driv
  • The Engine Control Module (ECM) constantly monitors fuel trim corrections and will flag a code when it determines that it cannot maintain a lambda mixture. The two codes you might see are system rich or system lean and they might be set for one or bo
  • For those of us who can troubleshoot, it's very satisfying to be able to figure out what to do when everybody else is at a loss. In a word, those of us who diagnose, pull steel and chase sparks are accustomed to solving problems for those people who
  • The average refrigerant charge in an older A/C system could be three pounds or more. Most passenger cars and light duty trucks today carry less than 20 ounces of refrigerant — barely more than one pound. So is efficient leak detection important
  • From run-flat tires to the implementation of tire pressure monitoring systems (TPMS), there's a lot of information today's technicians need to learn about. Even if you're not servicing tires, learning about them will help your bottom line, as many co
  • What are the challenges in designing a NASCAR brake system? A vehicle in motion accumulates kinetic energy proportional to its mass and to the square of its speed. So to stop that vehicle or to even just slow it down, that energy has to be transferre
  • Without spouting unnecessary scientific terms, let's loosely define the first and second laws of thermodynamics by saying that to begin with, heat must be generated by something at the expense of something else and then follow that to say heat moves