Hesitation during throttle

[TBentley]

Every once in a while I get a hesitation during throttle. It has a completely different sound to the engine at the time is occuring. Sounds like it is pulling a massive amount of air in. While this occurs the truck just lags and just doesn't want to go. Does anyone have a clue what it could be? 08 CC F250 w/ 6.4 stock.

[PowerstrokeTech82787]

Originally Posted by TBentley

Every once in a while I get a hesitation during throttle. It has a completely different sound to the engine at the time is occuring. Sounds like it is pulling a massive amount of air in. While this occurs the truck just lags and just doesn't want to go. Does anyone have a clue what it could be? 08 CC F250 w/ 6.4 stock.

have you had the most recent update installed by ford?
And do you notice whether the cleaning exhaust light is comming on or not?

[78-79FordMan]

i have some what the same thing . just off take off if i get on it. before the turbo spools up . that its was a normal thing as this is the first turbo diesel. don't think i hear the air just lag

[TBentley]

yes, I've had the update and it's not in regen. hell i can't even tell it's in regen now, if not for the indicator saying that it's in it. it doesn't do this often just every once in a while. Usually i just let off the throttle, wait a sec or two and then get back into it. thanks for the help!

[PowerstrokeTech82787]

I dont own a 6.4 never would. I notice throttle lag in them before updates, and after updates. Ive got 1 customer that ive done a radiator, front cover water pump and reprogram who swears up and down hill that at 65-70 on the interstate when he goes to pass a car/truck his truck has nothing and then it all of a sudden comes to life. Hell it was like that before it was reprogrammed. Ever notice if you flick the throttle say your in a parking lot, and you quickly tap it down to say 1/4 throttle, nothing happens, yet if you keep doing it all of a sudden itll take off like a raped ape? i just think its a processor lag, kind of like a computer when you have a few different things going on, like say your watching a youtube video, or playing a music video on youtube, while you have this site up browsing, and then be typing up a report or something else, and if you go back to the youtube window it seems to skip allthough the audio plays fine the video pauses then jumps ahead to match the audio? Pretty much same concept. Ill bet in a few years there will be a TSB to install an updated PCM that has a faster processor in it...

Ford doesn't have an answer for me...

[SJones]

Originally Posted by PowerstrokeTech82787

I notice throttle lag in them before updates, and after updates. Ive got 1 customer that ive done a radiator, front cover water pump and reprogram who swears up and down hill that at 65-70 on the interstate when he goes to pass a car/truck his truck has nothing and then it all of a sudden comes to life. Hell it was like that before it was reprogrammed.

I have seen the same thing in my 2008 Ford F-250 with the 6.4L POS diesel engine.

[TBentley]

truck is doing it a lot more often now. I don't know if the East Texas heat is causing it since we've been well over 100 degrees for the last 40+ days. To me I don't think it's throttle lag. It just seems like it's sucking air with lots of hesitation. just sounds completely different than when it's running normal.

[PowerstrokeTech82787]

Originally Posted by SJones

I have seen the same thing in my 2008 Ford F-250 with the 6.4L POS diesel engine.

haha you hate em too?

As for heat its been hot and humid no wheres near 100* up here in the north east but even in the winter when it could be -10 and snowing they just dont have instant throttle response. you say its sucking air and not accelerating? id start with a fuel sample make sure the filters are clean the fuel isnt cloudy, then id check fuel pressure, then id pull out IDS and see what short term fuel trims are for each cylinder during the event, VGT# during event, MGP and MAP psi readings, and every back pressure reading i could possibly do. after that id check under the turbo heat shield ive had a couple split apart that nobody even touched the turbos on. No soot there, then check the up pipe bellows for any carbon "stains" on them, check cac tube connections and use soapy water while the truck is boosted to see if theres a hole or leak at the cac tube connectors, then after that if everything is fine and checking out to be okay id say its normal deal with it or get rid of it.