2001 Chevrolet Venture Ls Mini Passenger Van 4-door 3.4l on 2040-cars

Auto blog

GM patent reveals new two-stage turbocharger

Modern turbochargers may be some of the best ever made, but performance is something that engineers are always trying to improve. According to GM Inside News, General Motors (GM) is hoping to alleviate some of the negative aspects of a two-stage turbocharger setup with a newly-patented design. The patent, that was filed on May 19, 2016, reveals a clever bypass system that allows the engine, a four-cylinder unit, to optimize both the low-pressure and high-pressure inlets for its respective functions. According to the filing, a conventional two-stage turbocharger setup is engineered to allow both turbines to operate simultaneously at low and mid engine speeds. At high engine speeds, only the low-pressure turbine works. The setup can't isolate either the low or high pressure side, which can impair low-end performance. GM's new two-stage turbocharger setup looks to eliminate this by linking the high-pressure turbo to the exhaust manifold through the high-pressure inlet duct. The low-pressure turbo is attached to the high-pressure turbo by a low-pressure inlet duct, which is linked to a connecting channel. A single actuator that is housed in the exhaust manifold creates a bypass that can opens the high-pressure inlet or close the connecting channel. Depending on what the engine load and speed is, the ECU guides the actuator—a single rotating spindle with discs corresponding to flanges on the high and low pressure sides—to isolate one of the two turbos. Isolating the turbos allow the respective inlets to be engineered for the best possible fluid dynamic performance. The setup should increase performance and decrease lag. There's no word on what car this setup will make an appearance on, but it will most likely be used in premium vehicles before trickling down to the rest of GM's vehicles. Related Video: News Source: GM Inside News, AutoGuide via GM Authority Cadillac Chevrolet GM Technology Sedan turbo patent engine turbocharging

GM will recall 3.5 million pickups and SUVs to fix brake issue

WASHINGTON — General Motors Co is recalling 3.46 million U.S. pickup trucks and SUVs to address a vacuum pump issue that could make braking more difficult and increase the risk of a crash. The recall, which covers 2014-2018 model year vehicles, including some Cadillac Escalade, Chevrolet Silverado, Chevrolet Tahoe, GMC Sierra, Chevrolet Suburban and GMC Yukon vehicles, was triggered because the amount of vacuum created by the vacuum pump may decrease over time, GM told the National Highway Traffic Safety Administration (NHTSA) in documents posted Wednesday. NHTSA opened a preliminary investigation into the issue in November 2018, and said it had reports of 9 crashes and two injuries related to the issue. It provided GM in July with additional field reports that prompted the automaker to open an investigation. The company did not immediately say on Wednesday how many injuries or crashes are linked to the issue but said it could impact braking in "rare circumstances." GM said dealers will reprogram the Electronic Brake Control Module with a new calibration that will improve how the system utilizes the hydraulic brake boost assist function when vacuum assist is depleted. GM said the vacuum assist pump, which is lubricated with engine oil that flows into the pump through a filter screen, can in some cases lose effectiveness over time, as debris such as oil sludge can accumulate on the filter screen. GM told NHTSA that prior model years used a different brake assist system design, and vehicles manufactured after 2018 were not equipped with the affected pump design. Recalls Chevrolet GM GMC

Nissan Leaf sets new November sales record, Chevy Volt drops again

When you talk to people in the plug-in vehicle industry, one theme you hear repeatedly is that the more plug-in cars that are out there, the better things are for everyone. One reason is that more EVs build a need for more public chargers, and more chargers mean more people see that plugging in is feasible. But there's still something to be said for old-fashioned competition, and in the sales race between the two long-running plug-in vehicles in the US, the Nissan Leaf is resoundingly beating the Chevy Volt for 2014. In fact, it won't be long before the EV's cumulative sales top the PHEV's. But that's a topic for another month. For now, we have the sales results from November. Unsurprisingly, Nissan set another monthly record (that is, the best Leaf sales in any November, the 22nd time in a row we've seen a monthly record) with 2,687 sales last month. That's up 34 percent over last November and up 35 percent year-to-date. Toby Perry, Nissan's director of electric vehicle marketing, said in a statement that, "Our 'Kick Gas' ad campaign and 'No Charge to Charge' launch in Chicago and Atlanta drove an increase in November Leaf sales. Even with gas prices falling across the country, consumers appreciate that the cost of driving a Nissan Leaf is still a fraction of that of a gas-powered car." Over on the Chevy side of the ledger, there were 1,336 Volt sales last month, down 30.4 percent from the 1,920 sold in November 2013. So far this year, Volt sales are down 16.4 percent and Chevy has sold 17,315 Volts in 2014. As we said last month, the Volt slump might be due to people waiting on the new version to make an appearance at the Detroit Auto Show next month before going on sale in the second half of 2015. So far in 2014, Nissan has sold 27,098 Leafs. Look for our detailed post of US green car sales in the near future. Until then, please discuss last month's Leaf and Volt sale in the comments, below. News Source: Nissan, General Motors Green Chevrolet Nissan Electric Hybrid PHEV ev sales hybrid sales