I know this question has been asked/answered before, but after searching I found that most folks have the "low power until warm" accompanies by other issues that I don't have, so I still scratch my head. It seems like possible injection stiction as described in other threads

2004 Ford F250 6.0L (recently purchased)

Problem: Low power until warm... 5 minutes or so. For those 5 or so minutes, the truck seems lazy. I can press the accelerator to the floor and he feels sluggish.

Notes:
-
- Truck starts fine when cold (but it is summer time, so its not THAT cold) Doesn't feel like its missing or stuttering at all.
- No smoke that I've seen
- Recently changed oil (15-40) with motorcraft filter. I plan on switching to Rotella T6 5-40 next oil change. Added pro-long and it help at bit...will try revx next time, or can I go ahead and add that too?
- Changed fuel filters (motorcraft)
- FICM voltage about 48.5 in all tests
- Don't have gauges yet
- Havent had a chance to check fuel pressure yet
- no codes according to my cheapo obd scanner.

I've also read that I should let it warm up for a while after cold starting, but how long should be enough. I dont feel like I should have to sit in my driveway for 10 minutes just because the truck doesn't want to get out of bed! Maybe I got spoiled because of the last cummins I owned.

The sluggishness sounds like injector stiction.

If I can add revx now, I will. Otherwise Ill wait till the next oil change and see if that helps. I've heard its good stuff, but is it just a band-aid? Or does the revx help remove the varnish on the spool valve? Would I just be buying time until the injectors possibly fail?

Where else should I be looking? Its annoying.

Thanks for the help!

 

Welcome to FTE temperoath.

I've moved your thread to the 6.0L Powerstroke Diesel forum where you'll get better and more accurate information and responses.

 

I would switch the 5W40 synthetic oil. If you still have issues, then add the Rev-x.

 

Pedal to the metal 5 min after cranking isn't a good idea. The RevX helped alot on my truck and can let you know if it's injectors or somthing else. I would put it in with a fresh oil change to give it the longest chance to work but in my experience, I idled the truck for 15-20min the evening I put it in (truck was warmed up) and it ran noticeably better the next morning. Is this a re-post? Seems fimilliar.

 

I have a 2004, and i am experiencing this same problem. I also changed the oil and both fuel and oil filters with motorcfaft products. I did just got the "blue spring" upgrade in today so hopefully this weekend I'll swap it.

I have to drive at about 25 mph for probably 1/2 mile before getting to the main highway and my truck still doesn't want to accelerate when I first takeoff. When i accelerate it seems like it wants to idle them it will slowly speed up, after the first time it is fine.

Does anyone know if this may be some sort of safety as to not damage the engine until it warms up? This weekend when it done it my EOT was 130 ECT about the same, are these temps not warm enough yet?

 

Thats what I think Ill do at next oil change. Hopefully it works, but even if it does Ill still be holding my breath while driving, and waiting on an total injector failure with smoke and roughness!

 

Yea...I dont dont go for pedal to the metal first thing in the morning though. Its mainly an annoyance that I avoid by making sure I have plenty of space between the next car when pulling out for work in the morning. I did notice that it makes knocking noise, it doesnt seem to affect anything at this point, but it sounds like it doesnt belong. Although, it is slightly masked by the other standard diesel clanks, so im not sure if its normal. Maybe its an injector about to go, but there are no codes yet. Oh...not a repost...unless I was sleep-lurking!

 

I bought my truck a few months ago and everything was fine, then it started having this low/no power when cold issue.

I was trying to remember when I started having this problem, I think it started after I changed the OIL and filter. Do you think the dealer could have put some sort of additive or maybe it could of had 5W40 oil in it, I put 15w40 motorcraft back in with the motorcraft filter?

Could this be caused by a bad injector?

 

Its possible that it could have had the issue before and 5W40 was in it, so it took care of it since its a "thinner when cold" viscosity and lubes the injectors faster hence no stiction. When the dealer put the 15W40 stuff back in it it came back since its a "thicker when cold" viscosity and takes longer to lube the injector to eliminate stiction. Thats why I plan on trying Rotella T-6 5W40 with revx additive at my next oil change to see if it helps anything. Hopefully the thinner viscosity and "special" crap in the revx will help me out. Otherwise, I think we both may be looking at an injector soon. We shall see!

 

Leaky injector orings can cause low power till they get warm and seal

keep close eye on the Oil check it once a week when cold see if its leval goes up or smells like Diesel fuel

when mine was doing it would make a qt every 2 weeks

Had all the Classic symtoms of a BAD Ficm with the exception of making oil
run rough
miss fire
shift wrong
low power
run Rough till warm

Reringed all 8 inject and problem solved

took me a few weeks to really catch on to what it was doing

 

I never noticed much of a difference between 15w40 and the others if the cold start is above 50-60 degrees, but below that 5w40 and 10w30 make a significant difference in cold starts and drive ability.

Josh

 

Thanks! I'll keep all that in mind as well!

 

I think I have some O rings to change. I checked my oil and it does have a diesel smell and it is over the hatching.

When I changed the oil i put in 15 quarts, after reading here I took some out until on the hatched area. After a few days I checked it again and it was stil high so I took some more out, and now it is high again.

Is there anything i need to watch for or be cautious with when changing the o rings?

 

The black one goes on top, white on bottom, copper on the injector nozzle, and lube them with clean oil or vaseline. I always cover the open side of the motor and crank it over to remove diesel from the cylinders to prevent hydrolocking. Make DAMN SURE you are not in the path of any diesel spray that WILL blow out of the cylinder when it turns over. Clean the cups of any excess liquid or debris and reinstall the injectors. ALSO remember to disable the fuel pump before cranking.

 

Are there any o rings that are better than the motor craft ones? I am assuming that the best way to disable the fuel pump is to just pull the fuse, is this correct?