ok i made a post before about the rough idle problem i have at cold startup. ( under 40 degrees. ) the engine fires up perfect, but about 5 seconds later it starts knocking like its lacking fuel.

i went to ford and they said theyd have to reflash it, but im not so sure i want that done.

on another thread SBV45 stated "They are doming out with a new flash in the spring because the Oct. flash fixed some quirky little idle things and changed shift points but at the same time they lowered fuel economy by 3-5mpg, reduced acceleration performance, made it louder and created new vibrations in the exhaust. Nice trade off for some idle problems. If you have not had the Oct flash DON'T do it. "

as far as im concernd, the engine can run rough for 5-10 seconds... i sure the heck dont want to lose power or fuel economy!

so should i just wait til spring? its only a few months away

ALSO i was considering disconnecting my batteries for 5-10 minutes, hoping maybe itll reset the computer

any ideas???

 

Don't flash it. If rough cold start idle [that quickly goes away] is all thats going on just leave it alone.

Mine does that and ...so what... The semi I used to drive did the same thing. IMHO if the driveability is great then why worry?
don't try to fix what ain't broke

 

I'm in a similar situation with a December '02 engine build date. Still have the original flash. I never had any romp-romp, rough idle problems until the truck's first oil change.

The 6.0L comes with 10W-30 from the factory, but the owners manual does not recommend "heavy duty towing" above 50 degrees F unless 15W-40 is used. So most service departments install the heavier weight oil.

When the heavier oil was installed a few months ago, the romp-romp idle mentioned on the forums first appeared. It's finally gotten cooler here in the NW and now, twice I have encountered a "dead-pedal" situation, where the engine RPM's won't increase when I put the truck into drive and try to climb the steep hill above out of my driveway. (only during initial cold engine operation)

If I let it warm up for a few minutes the problem goes away.

The '04 engines have a redesigned "wavy manifold" which improves the supply of oil to fuel injectors that is supposed to help the cold start problems. Apparently, the cold heavier weight oil does not flow fast enough through the '02 oil manifold fast enough to supply the injectors.

The October flash removes the pilot injection feature of the fuel injection system and other things.

I don't want the increased noise, the potential loss of fuel economy, loss of higher end acceleration and vibration at idle mentioned in this forum.

Since I don't tow my trailer during the winter months, I'm very seriously considering going back to 10W-30 to see if that solves the problem.

If changing to a lighter weight oil fixes the cold start problems, I would be tempted run that in the winter months and never reflash my truck's computer because my truck runs just fine in every other regard.

 

vision- if you DO run 10-30 and it solves the problem... PLEASE PLEASE PLEASE let everyone know! its is just annoying me.

 

Dont' reflash!!! Wait for the next one! My truck has the original factory flash and runs excellent! The only thing i need fixed is the high altitude problem (10,000ft).

It's just another one of those weird 6.0 things, mine starts smoothly, even at -7 degrees unplugged, with 15w40 oil, no romps at all. I don't see any problems with 10w30 in the winter if you're not towing anything, but I'm not a diesel tech.

Lastly, I don't think disconnecting the batts will cure the problem,
it will just re-learn, and start all over again.

 

My Dealer changed my oil yesterday (first time, 4000 m) and put 5W40 in it. I don't tow, but sounds like I have pretty light oil from what I am hearing.

When mine "diesels" up the hill, I have injector problems. Getting my second one tomorrow.

 

see

https://www.ford-trucks.com/forums/s...hreadid=181054