'The Model 3 scored 2,390 which is in the below average range', firm says.

A new report from investment banking company UBS has raised new concerns about the way Tesla is putting the Model 3 together, with analysts suggesting the issues can't easily be fixed.

According to the report, the teardown revealed inconsistent gaps throughout the vehicle, bolts missing in certain places, zip ties used around the car's construction, different bolts being used for similar roles, loose panel and glass tolerances, and tough-to-close doors.

Tesla says the car was an early production vehicle, and some of the issues have since been rectified.

"The engineers performed a fit & finish quality audit looking at 1500-2000 gap measurements in the vehicle in order to come up with an overall quality score. The Model 3 scored 2,390 which is in the below average range," UBS analyst, Colin Langan, said.

"In addition, the team independently rated the noise within the vehicle, finding the body/wind noise as borderline acceptable. Neither score is impressive for a car that is priced at $49,000."

Although some of the issues are easily fixed, Langan said others will be harder to wipe out.

"In our experts' opinions, the manufacturing issues around gaps and noise are much larger structural issues and do not lend themselves to being fixed quickly," he said.

"Their view is that many of the issues have to do with the basics of stamping out frame parts or the attachment thereof, which requires extensive retooling investment and shutdown time to fix."

Unsurprisingly, Tesla defended itself after the report was released, arguing it's rapidly improving build quality.

“Our customer satisfaction scores for Model 3 quality have averaged about 90% since January, with steady improvement through the year, even as the number of cars delivered has rapidly multiplied," its said in a statement.

"Tesla customers never have to worry because if they are unhappy with their car when they receive it, they can either give it back for a full refund, allow us to address any issues, or ask for an entirely new Tesla."