The Red Rose finished second in the Six Nations, but only after shambolically squandering a 31-0 lead against Scotland on Saturday.
England imploded so badly that they needed a stoppage-time converted try from George Ford to salvage a 38-38 draw at a stunned Twickenham.
Jones described it as “bit of a recurring theme for us” after losing three Tests – the opening two in South Africa last summer and at Grand Slam winners Wales earlier in this Six Nations – having been in promising positions.
It is a growing concern ahead of the World Cup in Japan, but he believes it can be traced back to the last such tournament in 2015 when hosts England infamously failed to get out of the group stage.
Jones explained: “It’s like we have some hand grenades in the back of a jeep and sometimes they go off when there’s a lot of pressure. We have a few of them and we’ve got to get rid of them.
“The team has probably had it since the 2015 World Cup and we’ve been working on a process to fix it. We will get it right, but it takes time.
“Whenever you have a difficult tournament or difficult games there’s always a lingering thought process there.
“Sometimes it takes longer than you’d like to fix it, but it is fixable. We’ve got a combination of personnel (to bring in), but I’ve got one person that’s going to help us that’s a bit of an expert. I’m not sharing that name with you now. I haven’t used her before.”
Asked what background or field she came from, Jones pointed to his head and said: “Up here, mate.”
Despite not being able to rectify the problem in more than three years, the Australian believes he will be able to expedite the process before their World Cup opener against Tonga on September 22 given he will have his squad for an extended period over the summer before heading to Japan.
Scotland retained the Calcutta Cup having beaten England at Murrayfield last year, but head coach Gregor Townsend admitted: “I have never been involved in a game like that as a player or a coach. Not many end up being 31-0, 38-31 and then 38-38 especially when you consider the team we were up against.
“It’s the most unusual game I have been involved in. I am very happy with the draw considering what happened first half.
“But the players are gutted not to have won, which seems incredible to think.”
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