The action began with an overnight sit-in at the Visteon plant in Belfast.
Fifty people who were sacked on Tuesday are on the roof of the Enfield plant. Others are holding a sit-in at the plant in Basildon in Essex.
The protesters claimed the company's former owner and main customer, Ford, had promised redundancy contracts which they now want to see honoured.
About 100 former workers spent the night at the Belfast plant.
Sinn Fein president Gerry Adams spoke to them on Wednesday morning.
He said Ford had a moral responsibility to do the right thing by their former employees.
He said his party would be lobbying the New York comptroller's office, which has pension funds invested in Ford, to bring pressure to bear.
The Visteon workers want their guarantees on pay and conditions, when the company was established out of the existing Ford plant nine years ago, to be honoured.
Workers spent the night at the Belfast factory
Northern Ireland Enterprise Minister Arlene Foster is to discuss the manufacturing situation with Employment Minister Sir Reg Empey.
She said: "The priority for myself, led by the Department of Employment and Learning, will be to skill and re-skill the men and women in west Belfast.
"This factory is closing, we must look to the future for those men and women.
"We know the manufacturing and construction sector are feeling very sore at the minute. They are having to deal with a very harsh economic reality and we want to help them in whatever way we can."
The administrators, KPMG, said it had no alternative but to close the factories.
Representatives from KPMG also spent the night in the Belfast plant.
Visteon had a total workforce of 610 in the United Kingdom. Five hundred and sixty five of them were sacked on Tuesday.
The company in the UK had been waiting to hear if Visteon in America would continue to prop up its three plants.
It said the remaining employees would assist the administrators in "the orderly wind down of the business".
It added that the UK business had not been profitable "since its incorporation in 2000" and Visteon UK's reported losses totalled £669m.
John Hansen, joint administrator, said: "The entire automotive supply chain has been under pressure for a number of years."
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