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Not The Transmission

As car owners, most of us know that engine or transmission problems are bad news. Finding out that either of these two major components is out of commission can cause immediate anxiety for any automobile owner. Symptoms of a weak or faulty transmission can often mirror similar symptoms of repairs that are not as serious—or costly, as a new transmission. Don’t fear the worst. Instead, read on to help identify when there might be a problem with the transmission or it’s something else entirely.

vehicle speedometer with check emgine light on

Transmission problems usually produce symptoms such as gears not shifting, gears slipping, bumpiness while the vehicle is in neutral, grinding gears, car shaking, burning smells, and/or transmission fluid leaks. While these symptoms often indicate problems with the transmission, it may not be entirely to blame. Some repairs are misdiagnosed as the transmission when in fact, it’s something else. To be sure, you need an expert on transmissions to inspect and determine what is wrong.

Shifty Business – Gear Shift Trouble

Car gear shift problems can send any driver into a panic, assuming their transmission is to blame. Yet, there are many other reasons that cause trouble when shifting gears. For example, if the catalytic converter or exhaust is clogged, the engine may experience a back-pressure problem, making it difficult for the transmission to change gears. An expert technician will need to perform an inspection to confirm the exact cause of the shifting problem. Shifting problems can also be caused by:

  • Faulty interlock switch. This is the apparatus that requires the brake pedal to be engaged in order to shift from park to drive or reverse. If shifting from park is troublesome, a faulty interlock may be to blame.
  • Shift Cable or Linkage may be corroded or coated with thick grease. Moisture, grease, and dirt can accumulate in or around the interlock and brake light switches and shift cable, making shifting troublesome. This usually occurs when the engine and transmission are After it and the surrounding components warm up, the gunk may become softer allowing the vehicle to shift from park.
  • Low transmission fluid combined with sluggish feeling and hard shifts. Transmission fluid is the lifeblood of your transmission, acting as a lubricant and coolant to keep internal components cool and well-oiled. Transmission fluid flushes are imperative to the life of your transmission.
  • Your vehicle’s internal computer may be malfunctioning. A car’s computer is responsible for communicating with the transmission to shift from park to drive or reverse and when to shift while moving down the road.

If you notice gears slipping, you may, in fact, have transmission trouble. Transmissions are designed to shift gears either manually by the driver or automatically. If the transmission is unexpectedly slipping in and out of gear, the transmission needs immediate attention. If this occurs, for your safety, do not drive the vehicle and have it immediately towed to a professional.

Go Car Go – Acceleration Problems with My Car

Car acceleration problems can feel like transmission troubles as well. However, combustible engines need the correct combination of air and fuel in order to produce power. When either of these elements is struggling, acceleration can be a challenge for the engine. The cause may not be the transmission and instead could be the result of air or fuel distribution issues or faulty sensors.

  • Air distribution troubles such as a dirty throttle body inhibit airflow, resulting in a poorly powered engine. Most modern vehicles are equipped with an electric throttle body controlled by the vehicle’s internal computer. A problem within the computer’s integrated circuit can make it difficult for the engine to create power. Vehicles with a butterfly valve mounted intake, fluctuate air delivery (depending on speed), and a problem within this system can result in poor acceleration. There are sensors in the throttle body that also get dirty and need to be cleaned or replaced when they are causing a running problem.
  • Fuel delivery problems that include a clogged or faulty fuel injector create misfires. Most fuel injected vehicles are equipped with one injector per cylinder. If just one injector fails, the engine won’t quit, but you will detect hesitation, shaking and vibrating, as well as a reduction in power. A lack of fuel pressure from a failing fuel pump or pressure regulator can also result in poor acceleration. Struggling fuel pumps starve the engine for fuel, resulting in poor acceleration.
  • Sensors that provide information to the vehicle’s computer, such as the mass air flow sensor can also contribute to poor acceleration. When these modules go out, they often trigger the check engine light to come on.

Because there are many components that could contribute to the loss of power during acceleration, it is best to have a qualified technician inspect the vehicle and perform a diagnostic test to properly repair the vehicle. While the air and fuel delivery or sensors may be the cause, leaks in vacuum lines, the emissions or ignition systems or engine problems can produce poor acceleration issues.

Shake, Shake, Shake – Car Shakes when Braking

If your car shakes or vibrates while you’re braking, there’s no need to blame the transmission. A healthy transmission is able to change gears smoothly. When an automatic transmission is struggling, you may notice a shimmying feeling as it engages each gear. More often, though, shaking while you have the brake pedal engaged, especially from the front end, is brake related. Other shaking, such as car shakes when idle, could relate to cylinder misfires or damaged engine or transmission mounts.

What’s That Smell – Leaks and Smells

Most transmissions are sealed units so if fluid is identified, there’s most often a problem. Leaks accompanied by a burning smell, however, can be cause for concern whether it’s coming from the engine, transmission, or elsewhere. Oil and other fluid leaks can cause a burning smell as they drip onto the engine or exhaust and burn off. If the leak is coming from the transmission, the smell can be different. Transmission fluid’s job is to lubricate internal components and act as a coolant to keep the system from overheating. Sweet burnt odors stemming from the transmission indicate the transmission fluid is no longer performing its task and gears may be overheating from too much friction.

Give Me a Sign – Check Engine Light

Perhaps the most obvious indicator that something is wrong with your vehicle, transmission or otherwise, is the check engine light coming on. The check engine light can indicate any number of issues under the hood. When the transmission has triggered the light to come on, usually sensors within the vehicle have recognized vibrations or other subtle problems that may not be immediately recognized by the driver. The check engine light may come on if the transmission is overheating, transmission fluid is too low, sensors are faulty, and for many other reasons. The best way to determine what the cause is, and how it should be corrected, is to consult with a professional technician. A technician will be able to run diagnostics and determine whether your transmission is responsible or just a minor repair is needed.