The news didn't get any better for Red Bull fans at Jerez on Thursday, with new recruit Daniel Ricciardo completing just three laps in the RB10.
Earlier in the week, Vettel managed only 11 laps over his two days of testing due to delays caused by a part being fitted incorrectly, a Renault energy store issue, as well as other problems said to relate to the installation of the power unit in the car.
As title rivals Mercedes, Ferrari and McLaren continued to set the pace and get a number of laps under their belt, Ricciardo's fortunes were much like Vettel's over the first two days.
The Australian only took to the track at lunchtime and completed just half a lap in the RB10 before he came to halt when smoke started escaping from the rear of the car.
After he got out and marshals blasted the car with fire extinguisher foam, the RB 10 was put on a flatbed truck and was carried off the track to the pits.
Ricciardo would return, but only to complete three laps before Red Bull called it a day once again.
Red Bull team principal Christian Horner and technical chief Adrian Newey left the track early in the afternoon without speaking to the media, though race engineering co-ordinator Andy Damerum released a statement which read: "We worked hard yesterday to make the changes it was felt were necessary to overcome the problems we identified and we were hopeful of a more successful day today.
"Unfortunately, the measures we took only partially solved the issue and, as with yesterday, it's more sensible to stop and dig deeper into finding a solution.
"It's obviously not where we want to be and naturally the whole team is frustrated by these issues.
"However, we're pretty good at bouncing back from this type of thing. This is where the whole team pulls together and I'm sure we will get these problems fixed."
Red Bull hope to finally get a decent amount of laps under their belt on Friday, but Ricciardo revealed there may not be a quick fix.
"They assume it is going to be something that they will have to go back to the factory and sort it all out," the Australian told Autosport.
"But at the same time they are trying and hoping that a quicker fix is ready for tomorrow. We will see.
"For nearly 36 hours pretty much they have worked on the car to try to get it running. We are a bit unsure right now."
Ricciardo is not concerned about the problems, however, and has confidence in the team to sort out any issues before Melbourne.
"We have still got a lot of time," he added.
"Even if we go to Melbourne still a bit whatever, it is a long season.
"These guys know how to win, that is important. I am sure sooner rather than later we will get it all together. It is still really early days."