Rough Idle/Stall/won't rev up 05 6.0L

[russf]

Hi, I have been browsing thro some of these forums to try and see if somebody has had the same issue, havent really found the same thing yet. I have an f350 6.0L and sometimes the vehicle will run really rough, as if it is starving for fuel. It will run rough like this until the point where it eventually stalls, and it will usually re-start but if it stalls enough it won't start for a minute and will have an extended crank period. When it starts to run rough the vehicle will not rev up at all, you can put the pedal to the floor and it won't rev at all. It first did this to me about two weeks ago, I ended up having to have it towed to my shop. Once got there it ran fine, i drained water/fuel seperator to check for bad fuel and there was some water in there so i figured i got some bad fuel until it did this to me again. What I have checked. btw it shows no codes.

FICM - 48-49v (should be good)
ICP - .8 to 1.2v at idle (should be good) tried disconnecting still nothing changed
IPR - 24% at idle (should be good)
Fuel pressure 50-55psi (good)
Accelerator pedal values change while pressing pedal (0-99%)
EBP - 115kpa (should be good)
EGR duty cycle - 0, valve position voltage shows closed, sometimes opens depending on how long it idles (normal)

This is stressing me out quite a bit, I'm a 4th year apprentice, I'm not really familiar with diesels but I'm trying to learn more. So far everything I have checked out, looks good. Today it ran great for me until I finally got it to run rough, and when I placed it into REV/DRIVE it got really rough but never ended up stalling on me today, I let it run rough for a few minutes in hopes that it would throw a code. I got a P0299 (TC/SC underboost), I ended up going to the VGT solenoid and found that the connector had been broken (maybe from prev owner?) and was eletrical taped to hold the male end to the female end of the connector. I unplugged it and ran great, re-plugged it back in and still ran great. I couldn't get it to run rough again after that for a while, now I was starting to think that maybe the VGT solenoid is sticking and causes too much back pressure and not let any air into the cylinders. Only thing I was confused on was that it ran fine with it plugged in and unplugged. I know that if it is unplugged it defaults to 85% duty cycle and opens up the vanes. I'm really hoping somebody might be able to help me out a bit on this, I've asked multiple people and nobody else really knows what to think about it.

[russf]

bump, I'm really needing some help and or suggestions. played around with my VGT connector today didn't take it out but it duty cycles on the scanner so I'm thinking that that might be ok. I got it to run rough again today wouldn't stall but when it did run rough WAC (wide open throttle a/c shut off) turned on to make sure it didn't stall and or get any worse. I'm really running out of ideas here.


FICM - 48-49v
ICP - 1-1.3V @ idle
ICP pressure 3000-4000kpa at idle
IPR 20-35%
Fuel pressure 50-55 psi
EBP good

everything is looking good.

One thing I found weird about my truck too, is that it doesn't have a MAF sensor. theres a connector for it, but no sensor. On the scanner it shows MAF_FAULT YES but it doesn't show a code. I don't think this is my issue tho either bcuz the entire time I've owned the truck it wouldn't of had a maf sensor and it ran good before. There is no code for a MAF sensor either, I really don't understand this. anybody else ever see this/experience this?

[russf]

bump.. looking for some help

[russf]

bump, went away for a while starting acting up again yesterday, tried replacing cam sensor due to code and misc injector codes being set once it got real rough. didn't help at all.

[Tyler]

When it stalls and has a long crank time, check the high oil pressure...

[Super duty 05]

I have 05 f250 192,000 mi. I have same issues, didn't make it home Friday night.
I have checked and changed everything I can think of. I am now looking at the fuel pump.... They say it must be 70 psi. Your 50-55 would be too low according to what I have been able to research. I know mine is not a HPOP issue and my FICM is fine.
Funny how this thread is not getting many responses. I will update if I get any news.

[russf]

this was quite a while ago when i was inexpierenced with the 6.0, i ended up needing 2 injectors no codes. What you found about fuel pressure is not correct. it requires 45 psi minimum.

Do you have any DTCS?

[Super duty 05]

Originally Posted by russf

this was quite a while ago when i was inexpierenced with the 6.0, i ended up needing 2 injectors no codes. What you found about fuel pressure is not correct. it requires 45 psi minimum.

Do you have any DTCS?

Contribution for cyls. 1&7. It ran great, parked it, started it up and it ran like crap. I drove 10 miles missing badly couldn't get up to 50 mph. Then it just seemed like it was running out of fuel. Just slowly got worse and died. I can get it started but seems like it runs on 3 cyls and then dies after about a minute. I can't believe I would loose all my injectors at the same time? when I do get it started it won't rev above 2000 rpm and smokes a little.?
Good to know about the fuel pressure though. Thanks!