A young couple who died from carbon monoxide poisoning had been sitting in a “souped up” Ford Fiesta whose modifications turned out to be fatal, an inquest heard.
Tom Putt, 20 and shop worker Nikki Willis, 23, were found dead in the £18,000 vehicle in December outside her home in Chelmsford.
An inquest on Monday heard that car fan Putt, an engineering apprentice, had carried out a series of alterations to his car to improve its performance.
He had removed the catalytic convertor from the exhaust and cut vents into the bonnet of his car.
However, a gap between the exhaust and the engine meant fatal fumes were sucked into the car via its fresh air intakes, the inquest heard.
The hearing in Essex was told that tests later revealed that carbon monoxide levels inside the car had been 1,000 times greater than the safety limit.
Detective Robert Kirby, who investigated the tragedy, said: “A unique set of events came together to allow this tragic incident to happen.
“A gap in the exhaust system where the exhaust meets the engine allowed fumes to escape.
“Compounded by the fact the car had had its catalytic converter removed (which normally dissipates harmful emissions).
“Vents underneath the windscreen wipers then in-took the emissions from the gaps in the bonnet.”
Residents told how they had heard the engine of Putt’s car running at around 4.30am on 5 December at Fox Crescent, Chelmsford, Essex. The alarm was raised at 10.30am.
It is believed the cold weather also contributed to allowing the fumes to accumulate.
Ford assisted Essex Police in tests and carried out analysis on Tom’s car and a factory issue model, which was when the dangerous level of toxic emissions were discovered.
Both deaths were declared to be accidents at Chelmsford Coroner’s Court by Coroner Caroline Beasley-Murray.
She read post-mortem reports that each victim died of inhalation of exhaust fumes including carbon monoxide.
Following her summary she said: “What a tragic tragic accident. She (Nikki) clearly was a young lady with a bright future in front of her.
“Again another tragic accident (Tom’s death). A young man with a bright future in front of him.
“I hope the families will be able to think of the happy memories.”
It is believed the pair met to have some food after Willis finished work on 4 December, and then drove around Chelmsford before parking outside her home.
Putt had driven from his home in Leigh-on-Sea and then took Willis back to her address in Chelmsford, where they were later found dead.
It is not known how long they were in the car for.
Vomit was found outside the vehicle on the driver’s side and in front of Willis’ home.
Police have been unable to trace how this will have got there and whether the two left the car and then returned at a later point.
Speaking outside court on behalf of the family and Essex Police, Detective Kirby added: “This was a tragic accident which led to the deaths of Nikki and Tom.
“Tom was not inexperienced. He had been an apprentice with Ford for over a year and had done work on his car previously.
“We would like to encourage people to please consider if modifications are worth the potential consequences.”
Neither Putt or Willis’ family have made a public statement at this stage.
Both are said to be looking to work with the police to warn people of the dangers involved in car modification.
Putt’s Facebook profile said he worked for Ford Motor Company as an apprentice. He was believed to have been a member of Essex-based car and bike enthusiasts club SleeperCrew UK, which paid tribute to him on Facebook.