My brother has a 2004 F250 w/6.0 that has 110k on it. Recently It has developed a bad miss @ idle I tested the FICM and it has 48V but the truck has never been to the dealer for a reflash.
So my question is does it need a reflash and if so it has to go to the dealer? He lives in Northridge CA. are there any independent and reliable shops that can do this?

 

One way to do a flash is to disconnect the batteries for a few hours then reconnect them.

 

You have to get the truck scanned first

too many un knowns

plus you will get to see the fault history

Bad miss at idle could be numerous things

sticking injector (1 or more)
Injector voltage too high (1-8)
Injector voltage too low ( 1 -8)
FICM voltage low while running
Bad Ground
Starving for diesel
etc.....

 

if it's doing it at idle and while driving it sounds like a plugged injector to me.

 

What?

The dealer can change flashes on the trucks to do a LOT of different things, this is why with a custom tuner you need your specific strategy. The dealer assigns this strategy to the truck... it's a PCM calibration. I think you're talking about clearing codes maybe?

I'm with this guy, there are too many unkowns, and frankly we can point you in the right direction but without properly diagnosing this, you're just going to end up throwing money at a problem you may not have. Test, Verify, Repair.

 

I was reading......and saw unhook the batteries to flash and about went crosseyed

I will say that an instant misfire like that I've found to commonly be the IDM but just like everyone else said , we cant even guess at a diagnoses with no information (even though that all we can do over the computer anyway )