I came across the phrase "What went wrong?" and I doubt if it has a correct form "What did go wrong?" or it would be already not idiomatic in this way. Is it idiomatic to use "What did go wrong?"?
Idiomatic Language – ‘What Went Wrong?’ vs ‘What Did Go Wrong?’
emphatic-polarityidiomatic-language
Best Answer
The second form is idiomatic with one caveat.
When we say it, we emphasize did. This means that we would also emphasize it in writing:
It doesn't sound right if we don't emphasize did. Without the emphasis, we would revert back to the simpler What went wrong?
When we do emphasize it, we are generally comparing it to something that didn't go wrong: