Auto Posted RSS Feeds only show as excerpts?

Hi everybody,
I am tearing my hair out over this. Until a few weeks ago, I posted RSS feeds using an autoposter. I receieved a comment from a long standing subscriber that my articles were only showing as excerpts.
I have changed everything there is to change, but whatever I do, the articles are only showing the first few lines?
I have changed the theme, plugins – one by one, altered the CSS Style.php, loop.php, The setting on the setting > Reading to full article.
I have tried all the “full article” rss posters. I have used the “full article” rss feed directories, rss feed converters to full article, all without any success. What is more annoying is that I set up an identical blog at the same time and that is OK. I have actually had them side by side on a split screen and gone through every .php file, every plugin and every setting. Everything is the same on the two blogs, and yet when i post rss feeds to one, they will onyl show as excerpts.
Please, can somebody tell me what else I can do to solve this?

Regards

Chris