Michael Ellis, 23, spent two weeks hitch-hiking with the teenager before they were found by police camping on a beach in the Norfolk seaside resort of Mundesley in August.
Lincoln Crown Court heard the pair vanished together six months after meeting on the social networking site Bebo.
Police had already warned Ellis, of Alexandria Road, Newtoft, near Market Rasen to stop seeing the girl after their relationship had been discovered in January.
Alison Cunningham, prosecuting, said the girl had also been reported missing then after becoming friendly with Ellis in an Internet chatroom.
"This followed a suspected failed suicide pact between them," Miss Cunningham added.
Police warned Ellis he would be arrested if he met the girl again before her 16th birthday and the girl's mother also banned her from seeing him.
But despite the warning Ellis continued texting the girl and began camping in woods near her home in Bourne.
The girl then told her mother that she was going to Skegness with a 17-year-old friend and an adult relative but planned to meet up with Ellis.
The girl was reported missing a day later by her mother and the pair were seen near Cromer on the Norfolk coast.
Following sightings in Mundesley the pair were finally found by police camping on the beach at 9pm on August 2.
But Mrs Cunningham told the court there was no evidence of a sexual relationship between the pair.
"That has been carefully reviewed by the Crown Prosecution Service and there are no charges relating to sexual activity."
Michael Cranmer-Brown, mitigating, said: "Not only did she willingly go on this trip, it was actively her idea.
"He wants it publicly acknowledged that he had no sexual interest her. He recognised that she was 14. He would say he was effectively looking after her."
But Judge Michael Heath told Ellis: "You abducted this child.
"It might have been her idea and I accept that she was entirely willing to go with you, but you had been in Internet chat room with her.
"You simply had no regard to how worried her parents would be, they were besides themselves."
Ellis, admitted a charge of child abduction between July 19 and August 3 and was jailed for two-and-a-half years.
He was also sentenced to an additional year after admitting making a hoax bomb call to Humberside police in April in an unrelated incident.
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