Ok my friend has a 2001 F350 4X4 lift 35inch tires and all banks mods. When he starts his truck for the first time when the engine is cold he gets bad romps. What would cause this? He says he has to hit the gas pedal to stop it.

 

For me, I switched to Rotella Synth oil 5w-40 and the romps went away. Also you can check out the GPR and glow plug system but the oil was my issue. The 15w-40 dino style in cold weather was too think to fire all the injectors and the romps would be pretty bad on my truck.

 

What he said

 

The OP is in the Republik of Kalifornia. Should be plenty warm for him and not need 5W40 synthetic.

 

His location say Mountain House.. might still be a tad chilly there. I know my cousins were reporting snow a couple of days ago in Col.

 

Location: Mountain House, CA

 

Yeah.. and if you look at the weather in Northren California, right now, in the Mountains, the high is 47*. That is at Castella, Calif. Just South of there, they are getting sleet..

 

Depending on how old the oil is, this could cause the romps too. Change braqnds of oil sometimes is a fix, from Rotella to Chevron Delo 400 type of brands. Synthetic would be a good way to go also

 

Ok I live in the bay area not in the mountains. Mountain house is a town,and I mean when the engine is cold not the outside temp sorry for the confusion. Once the engine is warm it won't do it.

 

Change the oil? How long has this been doing this?

 

it is off and on and he just changed the oil.

 

There seems to be a number of things that can cause the romps, both mechanical and software, from what I can gather. Most of the cases I've known about are eliminated by going to synthetic 5w40. Recently a list of the multitude of PCM calibrations was posted. IIRC, there were at least 20 potential calibrations. Perhaps there are different start-up parameters intended for different regions/climates? I don't know. Software is the only reason I could think of that would cause one truck to romp, and not on another. A buddy of mine has a 2000 PSD, equipped similarly to mine, and we both run Delo 400 15w40 (and will continue to do so). Mine would romp consistently in the low-mid 40's and up, whereas his never did. Mine at times would periodically romp in the low 60's. What made a huge difference on mine was the installation of the HPX line. Now I rarely if ever get the romps.

 

A bad ICP sensor will also cause romps even in hot weather

 

Me too, changed the oil when I got the truck, to rotella dino, and it strated to romp the next day, not even that cold................about a month later of romps change it to rotella syn 5w40 and no more romps even at colder temps..................

 

Checked icp sensor it is dry