I have a 01 ford F150 5.4L with 128,00 miles. The engine would shudder and get increasingly worse the faster I would go. The service engine light was on so I had it checked and I had a cylinder 7 misfire and a Code P0125. I changed all the spark plugs with no results. I then replaced the coil on cylinder 7 which seemed to have fixed it until the engine got hot.
My question is could a faulty thermostat or ECT sensor cause my truck to shudder (P0125 code)?
Any help on this problem would be appreciated.

 

Well yes. If you look up the code it will tell you that the coolant temperature is to cold.
Good luck.

 

Update....yesterday I unhooked the battery to reset the check engine light. It has not come back on though truck still runs rough.
I may change the thermostat anyway and see if that helps.

 

...You will see the light again.
...What you do by powering down the computer is cause a complete reboot of all the tables back to their normal design center values.
...Now the computer has to learn all your operating habits over again and retest all the system's parameters for faults.
...Until it detects the fault again the lamp will be off for awhile.
...It's always best to do a clear with a scanner than a complete reboot by power down but doesnot hurt anything but change how a trouble free system feels for drivability before and after reboot until enough drive cycles have altered the table values again.
Good luck.

 

Yesterday someone told me that my injectors could be dirty and advised me to run some Gumout cleaner thru my gas. I now have approx. 15 miles on since I put it in still no difference thopugh I suppose it needs more time.
Has anyone ever had a dirty injector cause this? Did I get a bad tank of fuel somewhere? The fuel filter was just changed not so long ago.