Cold Weather starting problems

[ElMemo]

Hello everyone,

Its that time of year when temps are getting low and raptors are not wanting to start. I have a 2010 5.4 3v 40,249 miles on it and every times the weather gets colder and truck sits overnight it has a hard time starting with a noticeable fuel smell coming from the exhuast. After it starts everything is fine absolutely no issues no codes. I have done relocation fuse, has new spark plugs, accel coils, new battery, fuel pressure checks out good, changed the fuel control that sits under the bed with an OEM one other than that everything is stock no tunes none of that. Has anyone one figured out why it has a hard start when the temp is cold after sitting overnight? Any help would be appreciated.

 

[jdubracing]

I also have the 2010 5.4, 135,000 miles. Same cold start problem that you described, with the strong fuel smell from the exhaust after it starts. After it starts it misfires and runs rough for 10 seconds, then smooths out and runs great. I cleaned the throttle body and MAF sensor, new plugs. I rented a fuel pressure kit and going to check that today. I’ll post if I find a fuel problem. Have you found a fix yet?

 

[matrix243]

I had an older 5.4L, just guessing but IAC cleaning? Always caused rough idle and a rich mix.