Angry passengers were stuck in limbo for more than five hours after a new Greater Anglia train heading to London broke down.
The 7.40am service on Tuesday from Norwich to London Liverpool Street service came to a halt at Forest Gate around 9.30am due to suspected brake faults.
It was one of the two new intercity trains built by Stadler, which are currently being rolled out on the line.
The disruption came on the same day Greater Anglia published figures saying 86% of intercity and rural users were satisfied with their services, with 89.66% of all the franchise's services arriving within five minutes of schedule.
Disgusted passengers reported a lack of toilet access, air conditioning and electricity while the train stood at a standstill for hours in the east of the capital.
Passenger Wayne Nunn, who works in London, said it was a "complete waste of a day".
Mr Nunn, 56, added: "It is an absolute nightmare - and how ironic is it that this is one of their new trains?"
Video footage on board the train showed police officers and Network Rail engineers passing through the carriage, while Mr Nunn said passengers were initially told to cross the line to a relief train by walking across a plank - which was later U-turned after not having a risk assessment.
Another commuter, Andrew Spence, added: "Communication was nonexistent, train staff were helpful but had no information to give.
"The train fitters came onto the train and could still not fix the train.
"Commuters are so fed up with the poor service from Greater Anglia and Network Rail. It is no longer viable to commute from Ipswich."
Passengers were later rescued from the train and taken to London Liverpool Street around 2.30pm.
A spokesman for Greater Anglia said a specialist team of engineers from Switzerland, the home of Stadler, to assist with the issue to help improve the reliability of the new trains.
A Greater Anglia spokesman said: "We are very sorry for the length of time that customers were caught up in this problem and the major inconvenience they have suffered as a result.
"Anyone who was on board should contact us for delay repay compensation.
"We will be holding a full investigation into all aspects of this incident to try to prevent any similar such problems in future.
"The broken-down train is one of our new intercity trains. We are working closely with Stadler, the manufacturer of the train, to improve the reliability of our new trains.
"They have dispatched a specialist team of engineers from Switzerland to assist us with this issue."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here