Engine output here in the UK reduced – by 14.5% year on year to 198,090 units – in April as the working month was shortened by a late Easter holiday break.
Year to date output remained positive – up 4.7% to 942,238 – following strong Q1 output.
Automakers exported 539,950 engines in first the four months of 2017 (up 57.3%) though April shipments fell 16.2% to 111,095.
Mike Hawes, SMMT chief executive, said: "Market adjustments and the later Easter break have combined to impact last month's production levels but overall engine production remains healthy year to date.
"UK engine plants are deeply integrated within the European supply chain where parts cross borders many times before a vehicle is finished.
"Like the wider industry, to guarantee future growth we need the next government to safeguard the conditions that have made us globally competitive, keeping us open and trading and delivering an ambitious industrial strategy for our sector."

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