Congratulations, SSCOWBOY... you win the Internets today!

 

Haha! Well she puts up with me so I guess she can fly her broom whenever she wants. Getting back to my truck, following some of the pinpoint recommendations, there is mention of the alternator possibly contributing to the shudder. A bad diode or such. The constant voltage coming out of mine hovers at around 13.8v. I noticed that occasionally it will drop to near 12v. Curious what the normal output should be. I would think that it would be mor along the 14v range. Also, I saw in another thread where pulling the VCT connectors caused the shudder to go away, by producing an open in the circuit. Any validity to that? I hate to keep this thread alive unnecessarily and will move this to its own if need be. BTW... If I watch the timing on my code reader, when it shudders, the timing flutters back towards 0 degrees then as you accelerate it advances to the correct timing and smooths out.

 

Are you able to see AFR when this occurs? Does it go lean? If fueling was dying then timing will drop.

 

I just upgraded to the torque pro app so I'll look later today to see if the ratio changes significantly.

 

I have a 2000 f150 triton xlt. This truck has a 4.6 v8, and is 4x4. The transmission is a 4r70w. I recently, had this transmission rebuilt at a transmission shop. The mechanics finished putting in the transmission and I test drove it yesterday. The OD continually blinks, the transmission won't shift, the speedometer and rpm rev upward as if I were giving it a lot of gas. I can be going around 5 mph and it will show 90 on the speedometer. The truck started reving as if the gas pedal was stuck, but it wasn't. The truck then started sputtering and jerking. After all this the engine stalled. I could restart it fine and it would go in gear fine. But the truck will not shift.

 

I had the same issues with my 2007 f-150. A good item to check are the ignition coils. A bad coil will cause a misfire at lower rpms and cause the truck to shudder, almost like there is a transmission problem. A lot of times, it will not kick the CEL on and there is no record of the misfire on the OBD scan either. Im not 100% percent sure why thats the case. Maybe the coil is providing spark but not at the correct voltage? Anyways, it is a common problem as well a the spark plugs. Ive had my plugs changed in the last 20,000 miles, and Im going to check those as well to make sure they arent loose. After that I'll inspect the coils for obvious problems and try replacing those coils first. If that doesn,t completely solve the issue, then maybe I'll change out all of the coils. Some parts stores have the coils for around $40 and have a lifetime warranty on them. In my opinion, that would be money well spent if you can have them replaced free of charge if/when they fail again.

 

Had the dreaded shudder when truck (05 5.4) got into OD. Took it to mech, and found no codes thrown. Since truck has 64K on it, I decided to have him change plugs. Went with Motorcraft SP 546#, instead of old SP 515#. Apparently (according to Amazon), these are superceding old style plug. Anyhow he broke 4 off, and got them out. Took truck out for test drive, and couldn't make it shudder anymore. But when I hook the boat on, that will be the real test. If it reoccurs, I will be changing coils. Can get them for half of what mech quoted, and I'm sure I can change them.

 

Or monitor using mode $6 and see which cylinder, if any, is misfiring.

 

Buy torque pro app get blue tooth adapter for code reader . Pair it up with phone . look at real time data . It will give you raw data that is there and may not have a enough percent to set code . Each cly will show whether it has some small misfires .
Failure to change boots on plugs or some other plug mistake can cause this . Mc sp 515s bad out of box new plugs sp546 . Realce all boots torque all plugs 25 to 28 foot pounds .Be careful with anti seize , and dielectric grease it is an insulator .
Cop contacts should be cleaned . Best to clean spark hole out with carb cleaner get carbon out .
Then there are the injectors, by moving parts around you should find your misfire part .