Your good description makes me think it is a potentially terminal fault.
I was recommended to try an acredited Epson repair outfit when I was having trouble with paper transport in an EPL 5800.
The reception lady was fairly terse, and offered a premium number at around £1.00/minute, and a promise that I would not be kept hanging on.
I thought a bit and decided to try it.
In a few seconds under 2 minutes I had a technician's diagnosis and a blow by blow how to clear the problem.
It was a while back, but at the time I was well pleased to have a good workable answer.
Equinox Maintenance Group Ltd (Tewkesbury) may be worth a premuim rate call.
Their normal office number is 01684 290000