Got a couple of questions. 1 I have a 5.4 supercrew that has a miss or at 45 to 50 mph it doesn't seem to do this any other time any thoughts?
2. possible oil leak no smoke or visible leaks down below readable level only 2000 mile from last oil change? not sure where it is or a piston ring leak??
3. possible transmission/ transfer case seal leak both are full and seem to be cross contaminated? it has just over 91,000 miles on it trying to see what it would cost to fix all of these issues.....thanks for input Mike

 

whats it doing to make you think you have a miss?

 

1- Change the spark plugs if they have never been changed.
I have an 01' F-150 S/Crew w/ 5.4L and it did the same thing until I changed the plugs.

2- Check your positive crankcase valve (pcv). Mine started to burn oil and I changed it. Took care of the problem.

3- I have no idea as mine is two wheel drive. Sorry

Good luck with the repairs.

 

When i accelerate at around 45 mph theres is a very quick hesitation and if press it a little more it'll do it again I'm not seeing any RPM drop when it does tough...I'm supposed to take it in tommorow to have it looked at for about $250.00 just to see whats going on with it... thanks for your response Mike

 

sounds transmission related. a miss wouldnt happen at one set speed. sounds like an issue with OD.

 

Let us know what they tell you.
Your miss is one low output coil. There is an explanation for this.
Lets see if they come to the same conclusion.
As for oil loss issues, can't tell from here.
Good luck.

 

I will be taking it in this Wednesday to have it all checked out.I will keep you posted on what is said I did have the motor flushed back late January because there was moisture in the oil filler tube and I changed the cap as well

thanks so much Mike

 

Update there is a miss in the engine so now there looking into whether it the ignition system or possibly the torque converter...fun fun fun c-ya Mike

 

That's neat!

Tell them to look at Mode 6 and the missfire monitors or do a stress test on all the coils to pick out the coil that is causing the missfire.
The reason you have the missfire condition in OD is when the EGR opens, the mixture goes lean and requires higher coil voltage to fire the lean mix.
If a coil is low or marginal, a missfire results.
This usually does not set a code because it's not a hard fault not in long enough to be logic determined, a fault..
Good luck.

 

Bluegrass Thanks again I will tell the mechanic about this...c-ya Mike