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Is the skill of rev matching being lost to computers?

If the ability to drive a vehicle equipped with a manual gearbox is becoming a lost art, then the skill of being able to match revs on downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. The usefulness of rev matching in street driving is limited most of the time – aside from sounding cool and impressing your friends. But out on a race track or the occasional fast, windy road, its benefits are abundantly clear. While in motion, the engine speed and wheel speed of a vehicle with a manual transmission are kept in sync when the clutch is engaged (i.e. when the clutch pedal is not being pressed down). However, when changing gear, that mechanical link is severed briefly, and the synchronization between the motor and wheels is broken. When upshifting during acceleration, this isn't much of an issue, as there's typically not a huge disparity between engine speed and wheel speed as a car accelerates. Rev-matching downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. But when slowing down and downshifting – as you might do when approaching a corner at a high rate of speed – that gap of time caused by the disengagement of the clutch from the engine causes the revs to drop. Without bringing up the revs somehow to help the engine speed match the wheel speed in the gear you're about to use, you'll typically get a sudden jolt when re-engaging the clutch as physics brings everything back into sync. That jolt can be a big problem when you're moving along swiftly, causing instability or even a loss of traction, particularly in rear-wheel-drive cars. So the point of rev matching is to blip the throttle simultaneously as you downshift gears in order to bring the engine speed to a closer match with the wheel speed before you re-engage the clutch in that lower gear, in turn providing a much smoother downshift. When braking is thrown in, you get heel-toe downshifting, which involves some dexterity to use all three pedals at the same time with just two feet – clutch in, slow the car while revving, clutch out. However, even if you're aware of heel-toe technique and the basic elements of how to perform a rev match, perfecting it to the point of making it useful can be difficult.

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2021 Cadillac Escalade, GMC Yukon, Chevy Suburban/Tahoe recalled for stall risk

General Motors is recalling just shy of 15,000 2021 Cadillac Escalade & Escalade ESVs, Chevrolet Suburbans and Tahoes, GMC Yukons and Yukon XLs that were shipped with fuel pumps that were built with a batch of what may be faulty electronic control modules. A pump with a bad module can result in intermittent function, resulting in drivability issues and potential stalls. No serious incidents or injuries have been associated with the issue.  GM says it discovered the issue after analyzing early recall data for the 2021 model SUVs and discovering an unusually high failure rate for fuel pumps manufactured by a single supplier – Vitesco. The company was able to identify the batch and initiate a recall campaign targeting just those vehicles.  "After reviewing the field data, GM determined there were 617 potentially relevant complaints, which were received between April 15, 2020 and August 24, 2021," the company's recall report said. "229 of these complaints reported a stall while standing or moving. No accidents or injuries associated with this condition were found." Any SUVs built with pumps from that batch but not yet sold are being held at dealers for replacement parts. It may take some time for GM to source replacements due to the ongoing electronic parts shortages.  "We are working with the supplier to obtain the required parts as quickly as possible," GM said in its notice to dealers. "When sufficient quantity of parts are available, the recall bulletin will be released and dealers can begin repairing vehicles."