FICM replaced, idle issues
About a month ago I was having cold start issues with my 2004 f-350. It has the 6.0L in it. I took it to the dealership and they told me the FICM was bad. I had them replace it and they said they loaded it with the most current software. Since I picked it up I've been having several new issues that were not present before. When I start it cold it will idle for five minutes or so, then idle up to about 1,000 like normal, however, it will begin to have a very rough and sometimes surging idle, stumbles and misses. It will also not drop off the high idle when the brake is depressed. Eventually when it warms up the idle does come down, but still surges now and then. Even when it's started warm it tends to go to he 1000 rpm high idle and wont drop when the brake is pressed. Any ideas? I've had it back to the dealer twice and they are scratching their head. No codes present.