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DETROIT (Reuters) - New technology to stream music into dashboards or boost fuel efficiency is making cars less reliable, although electric cars such as the Tesla Model 3 and the Chevrolet Bolt should fare better than many conventional models, Consumer Reports magazine said on Thursday.

The magazine said its survey of 640,000 vehicles showed that all-new vehicles or models with newly updated technology are more likely than older models to have a “wonky engine, a jerky transmission, or high-tech features that fail outright.”

Electric cars do away with many of the mechanical systems that prompt consumer complaints about conventional cars, the magazine said. Tesla Inc's TSLA.OModel 3, despite recent production problems, should have "average" reliability because it relies on technology already used on the older Tesla Model S, Jake Fisher, the magazine's head of automotive testing said on Thursday at a meeting of the Detroit Automotive Press Association.

The Bolt is the most reliable car in General Motors Co's GM.N Chevrolet brand, he said.

Tesla in a statement on Thursday criticized Consumer Reports because it previously declared the Model S “to be the best car ever and then revoked the rating after being questioned by Tesla skeptics.” As for the Model 3, Tesla said “it’s important to note that Consumer Reports has not yet driven a Model 3, let alone do they know anything substantial about how the Model 3 was designed and engineered.”

The magazine’s annual survey of new vehicle reliability predicts which cars will give owners fewer or more problems than their competitors, based on data collected. Its scorecard is influential among consumers and industry executives.

For the fifth straight year, Japanese automaker Toyota Motor Corp 7203.T placed first in the magazine's ranking with the most reliable vehicles on average. General Motors Co's GM.N Cadillac brand was last among 27 brands ranked. Tesla ranked 21st on the list.

With many new cars, customers complain about problems with continuously variable transmissions and eight- and nine-speed gear boxes designed to boost fuel mileage, Fisher said.

Hard to use infotainment systems also continue to annoy customers, Fisher said. But over-the-air updates are helping automakers alleviate problems more quickly, he said.