Question

does this sentence make sense?

He had to leave the park soon because he left his three cars' engines running.

Answer 1

No
"had" is past tense
"soon" is future tense
"left" is past tense
"soon" needs to be changed to future tense for the sentence to make sense

Answer 2

sorry i meant "soon" needs to be changed to past tense

Answer 3

Or simply remove “soon”!