Hey guys,
My grandfather has a 2003 f250 6.0 with 107k on it. For a while now the truck is rough starting and lopes for a few seconds when cool. After I give it some gas it smooths out and otherwise runs perfect. We recently went on a trip and noticed that after pulling off the highway for 500 miles that it had a rough idle. The throttle response is great and no smoke other than normal. Also on that trip we noticed that the mileage dropped to 11 mpg going 70 constantly and towing 3000 pounds. He says that normally the truck consistently gets 17-18mpg empty. Is this normal?

 

Welcome to FTE 87classic460 The mileage will vary depending on conditions like, fuel quality, tire pressures, road surface, grade, and drag of the item being pulled.

Rough cold start can be many things, quality of oil used and change intervals. FICM (Fuel Injection Control Module) solder becomes brittle or loose over a period of time. ICP Sensor (Injection Control Pressure) may be leaking, located under the turbo on 2003 and early 04 model years. Hard starts when cooler weather has arrived could be the Glow Plug Module Relay.

If you can give us more information, we may be able to help you figure the problem out.

 

Definitely test ficm. There is a detailed write up in the tech folder

 

Thank you maximum,
The tires on the truck and trailer have all been aired up the trailer is a 24ft center console boat and doesn't produce much drag. Also the roads are relatively flat. Prior to the trip the oil, air filter, and both fuel filters were changed as well as all 4 shocks. The oil is rotella 15w40. I'm pretty sure the icp was replaced 2 years ago. We could smell diesel in the cab before they fixed it. Also the truck starts right up without a hitch even in 30 degree weather without being plugged in, and never has a problem except for the rough idle for a few seconds after start up. Also the idle gets rough when we stop after 6 hours of continuous highway driving. Any other info I can give?

 

EGR valve would be my first choice, followed by the ICP sensor.

Josh

 

Do you still smell diesel/exhaust in the cab? Read through our Tech Folder located at the top of this forum for more information and check your intercooler boots since it is an 03. Lost boost pressure will go a long ways that you may not notice.

Can you read codes? Just to let you in a little secret, you can unplug the EGR valve on the MY 2003 with the truck shut off and it not will throw a check engine light, it is not recognized as unplugged in our strategy. Once unplugged, the EGR valve will be in the closed position, drive it and see if anything changes. Your symptoms of rough/smooth idle, surging, point to ICP Sensor.

 

No the diesel smell was solved. I can read codes at my dads house so when I get the chance ill take it there. We're actually still on the way home from Canada so when I have time ill unplug the egr. Where is that plug located? How do you test the icp? Thank y'all so much for your time

 

At the front of the engine right beside your oil filter, just unplug the EGR. This picture is how some of the guys remove the EGR with a wire.

 

Likely his EGR is carboned up and not fully closing, causing hard cold starts and erratic hot idle.

Disconnecting it will not do anything.

Josh

 

Never know.... just giving him suggestions to try while they are on the road.

 

Could be dirty / Sticking Injectors ( Stiction ). Do you use Diesel Kleen fuel additive and oil additive like Archoil or Rev- X ? What kind of oil do you run? These things love 5/40 Synthetic like Rotella T- 6. Oil and filter change every 5 K miles?

 

OIC...

Josh

 

My '03 is having similar symptoms, and I suspect a leaking ICP sensor is probably the cause. I haven't looked at it yet. I plan on checking it when I pull the cab to install my studs and egr delete.

I hope to get a chance to work on it this weekend. I will post what I find if that will help.

 

I have the same issues. I would get a rough cold start that would go away after about 5 seconds from starting. GP's checked fine, ICP was replaced, full maintenance twice (been living with it for a while). Also after about an hr of driving I would get a random rough idle. I would get a contribution code for #5. I switched to 5w-40 synthetic and it eliminated my cold start issue and my hot idle issue. Just speculating but I wonder if the varnish on the spool gets warm enough to get kinda tacky (hot idle problem) for the idle issue. Sometime I want to clean my spool valves but synthetic will be the treatment for now.

 

if you feel like crawling under it you can see if it is leaking.

the rough idles and sputtering may occur with the icp ipr and or the egr..

those are the common symptoms from my knowledge i replaced my icp and #7 injector and my girl seems to be running awesome. the egr is a pain in the butt, and i think an egr delete is also a great solution. the picture above shows how to pull it.

two bolts one clip. make sure not to get any fluids in the holes as it can cause failure. the two 8mm bolts are torqued down to 21 lb ft i believe and from what i heard it isnt a big issue if seated properly that they arent torqued, but i would just for the better mind.

\icp ipr egr.. check all those first.