Jason Matthews, 40, of Wolverhampton, parked his Saab before the Greater Manchester Marathon on 19 April.
He said he went back at the weekend and spent the "best part of five or six hours looking around Trafford Park".
Mr Matthews said he had now been told the car was found in the Salford Quays area after a man who saw a newspaper story about it went looking for it.
The marathon runner said it was only his second time in Manchester and he was following diversions while driving his Saab 93 Sport.
He said after the marathon he spent about 90 minutes or longer looking for the car and went to police and registered it as a missing vehicle.
Mr Matthews, who works in Bridgnorth, Shropshire, said he was told on Tuesday afternoon that a man had found the car after reading an article in the Manchester Evening News.
He said: "I'm very grateful.. It's a big burden off my shoulders.
"(But) now I've got the trouble of going up there on the train to retrieve it."
He said he would make a donation to a nominated charity and would see if the man who found it "has a charity in mind".
Mr Matthews said: "It's something I'm going to do out of courtesy. Someone's taken the time to look for it."

Then playing for Walsall, the 24-year-old won his first senior cap for Wales in their defeat by Ukraine in March, giving him the chance to rub shoulders with the duo.
Injury dashed his hopes of joining them at Euro 2016, however.
"They constantly want to improve and get better so that's something every footballer should apply to their game," Bradshaw told BBC Radio Wales.
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Wales have been buoyed by the success of Arsenal midfielder Ramsey and Real Madrid forward Bale in 2016 as they reached the semi-finals of the European Championships, their first international tournament for 58 years.
Bradshaw, who has scored three goals in 19 appearances for the Tykes this season, puts the success of the pair down to two factors.
"You watch them train and you watch them play and you try to pick their brains about how they managed to get to that level," he said.
"A lot of it is natural ability and natural talent, but the thing that strikes me is their hunger; their hunger to want to improve even though Gareth's playing for Real Madrid and he's a massive part of his country's team."
Bradshaw says he was "gutted" to miss out on Wales' memorable Euro 2016 campaign after a calf injury ruled him out of contention.
The former Aberystwyth Town player has since concentrated on boosting his future Wales hopes by performing well for his new club Barnsley.
"It was incredibly frustrating, with hindsight as well, at how well the lads did," he said.
"I was incredibly proud of the boys and how impressive they were at the Euros. I was gutted, but that's football. Unfortunately that was part and parcel of the game.
"But I picked my head up and managed to get a move to the Championship and I'm just trying to improve. It hurt for a while. It took for the majority of that summer for me to get over it.
"I was watching all the games and cheering the lads on from afar, but it was invaluable experience for me to go away to Portugal although I didn't manage to train that much because of the injury, it's all experience that I've enjoyed and hopefully I can put it into good use in the future and hopefully one day I'll get an opportunity again."

The camera and medical equipment firm brought the case against ex-chairman Tsuyoshi Kikukawa and 15 others.
A Tokyo court found Kikukawa and five others liable for $529m.
The ruling comes comes six years after former chief executive Michael Woodford exposed his colleagues for falsifying accounts to conceal losses of $1.7bn.
The scandal was one of the biggest financial frauds in Japan's history, but Kikukawa and two other executives who pleaded guilty never went to jail. Instead, they were given suspended sentences of up to three years.
An Olympus spokesman declined to comment, saying the former employees could appeal against the ruling.
One of the six men found liable by the court has since died, but his family could still be held responsible for his share of the damages, according to the AFP news agency.
A marathon runner has been without his car for eight days after forgetting where he parked it before the race.
[NEXT_CONCEPT]
Barnsley striker Tom Bradshaw says every footballer can learn from the examples set by Wales stars Gareth Bale and Aaron Ramsey.
[NEXT_CONCEPT]
Six executives sacked by Japan's Olympus have been ordered to pay more than half a billion dollars in damages after a massive accounting fraud.