engine bucks at times, please help

[notchcrazy]

so my 04 f350 bucks at times while im driving, but it doesnt happen all the time. out of the blue, it will jump and the rpms will rise then fall, rise then fall, like its down shifting then up shifting, but im going the same speed. weird thing too, if i stop, put it in neutral, and rev it a couple times, it seems to stop. ive brought it to ford before but b/c it doesnt happen all the time, they dont know how to diagnose it. most of the time it drives normal, but at times it will buck. and it doesnt matter if its hot or cold, itll do it whenever it feels like it.

ive changed the fuel/water seperator filters, but other than that i dont know what to look for.

is there anyone that could help? thanks

 

[mxrider39]

Hey notchcrazy,
I too am having somewhat the same problem ( doesn't always do it) but mine seems to be the engine missing or falling on it face. I am taking my truck to the dealer wed to get checked out. While talking to the mechanic on mine he said it could be injector or the turbo, probably not your problem. But he did also mention I belive the map sensor, can't remember exactly. He did say that this controls almost everything and could make the truck do werid things.

Just my input.

 

[Deviant Diesel]

There was a computer reflash put out for the '03-'04 6.0L to fix the problems you guys have. They never did a recall, but it was a pretty big issue last year. My dad and 2 of his buddies all had the same problems and they ended buying back one of their trucks.

 

[04X]

Happy Holidays everyone!

I've had a somewhat similar problem. Mostly cold(er) engine temp and random events, my '04 6.0L Excursion RPM's would pop up and then the thing would run like it wanted to stall out. The dealer replaced 4 injectors, followed by EGR, EGR cooler replacement, and manifold cleanout.

I have since had a warm engine condition that happens randomly. Last night was the most recent case. After a 2hr trip home (highway) I idled down the exit ramp and the engine started to stumble at the stoplight(s).

When this happens and I'm not in a 'stall safe' spot I bump it to neutral and take the RPM's up to counter-act and then it settles out within a few minutes.

The dealer says the computer is not throwing a code and they could not duplicate the event. So...I'm at a loss.

Any suggestions?

Thanks

 

[Deviant Diesel]

Read my post above. This is not a problem that the dealers will tell you they had, the reflash was basically told from one customer to another. Just take your X to the dealer and tell them you want the '03/'04 PCM reflash done. I'm 99% sure this will fix your problems.

 

[powerboatr]

also
check the throttle wiring that runs thrugh the firewall up to the ecm, there was a chaffing recall, its a bit old but still effective, some trucks were missed i am sure. also the brake light switch assembly it can become loose and cause an errant brake light contact which disengages the tc and causes rpm to speed up or wander up and down.

 

[jschikore]

Same Exact Problem as 04X

I am having the same warm engine conditions as 04X.

Has anyone come up with a solution????

HELP!!

 

[fordtrucknut]

EGR?

My truck was doing this a few months ago. One time I was sitting at a light, my foot was barely on the brake. Out of no where, the RPMs spiked up for a second or two and then it almost stalled. Meanwhile I almost ran into the car in front of me. I was a little upset so I left the line with my right foot halfway to the mat. There was a cloud of smoke. So I pulled over, shut her down and unplgged the EGR valve. It has never acted up again.

 

[jschikore]

Thanks for the advice! I just took the truck to Ford in Fairfield and the tech. mentioned that the EGR valve may be sticking and may need to be cleaned and or replaced. I hope this will end my problems. I will keep everyone posted on the outcome just incase other members experience the same problem.

 

[jschikore]

Problem fixed for now. The Ford dealer in Fairfield todl me that there were numerous recalls and a new Flash program that had to be updated that the previouse dealer that serviced the truck did not see or just got lazy and did not update, I will never know!!

The new Flash progam runs a pump for 30 seconds after the engine shuts down to drain oil from the injectors or turbo.