Lost

[BlackSTX]

Before you go replacing coils, if replacing them didn't change the problem initially, they're probably okay, don't waste money that you may not need to.

As suggested, see if you can get that info requested by Longshot. Have you questioned the dealership that charged you up the wazoo for a ton of work without correcting the problem? I'd try hitting them up for not fixing the problem, that's far more important than replacing the coils again.

[osprey]

Sorry to be a 'Johnny-come-lately' to this problem, but I might have a solution to this problem.

What it sounds like, to me, is that your camshafts may be in a retarded positon by one or two teeth, causing the poor performance. You could also have a problem with cam phasers that are not advancing the cam timing during acceleration. These problems would not be apparent in no load acceleration (transmission in park or neutral), but would be very apparent in acceleration under load.

I would definitely have both the camshaft timing checked, and have the cam phasers checked for proper operation.

I know, from personal experience, that when the timing gear started to go out on one of my previous vehicles, the cam timing retarded one tooth. You used to be aable to tell this because the initial timing woudl be retarded when read from the balancer with a timing light. You would then advance the initial timing by resetting the distributor, and everything would seem fine, until it jumped another tooth and retarded the camshaft further, and even then with the timing reset, the engine would be very weak.

Hopefully, this information will help you get your truck back to 100%.

[Power Hungry]

To further expand on Osprey's thought, the Cam Phasers are notorious for failures on these engines. It's not skipping a tooth, per se, but it sure feels like it.

Two things can help identify this issue:

1) Startup clatter - When starting the engine, the cam phasers will clatter loudly and it takes time for the oil pressure to build. Even after running, the phasers will still clatter a noticeably at idle.

2) Bearing "dust" in the oil - After running for a few minutes, pull the dipstick and check for aluminum or bronze "dust" or "glitter" in the oil on the dipstick. This is especially noticeable if the oil has 2000+ miles on it. Any glitter on the stick is a serious problem.

As I understand it, the camshafts are the first components to receive oil and any problem with the cam phasers causes poor lubrication to downstream components. If the phasers go out, the crank and rod bearings are not going to be too far behind.

I really am not trying to scare you with this information and it's quite possible something as simple as a bad O2 sensor or something similar that's causing your drivability issues, but it's definitely worth taking a look just in case.

I hope this helps.

[osprey]

Thank you, Bill, for clearing up my idea.

Coming from over 35 years of working on engines from a 59A flathead in a '37 coupe to today's modular engines, I knew what the symptoms sounded like, but wasn't sure what exact component was the culprit. Hearing about this problem makes me even more leary of the 5.4 3V and the cam phasers.

[Jackpine]

Originally Posted by osprey

Thank you, Bill, for clearing up my idea.

Coming from over 35 years of working on engines from a 59A flathead in a '37 coupe to today's modular engines, I knew what the symptoms sounded like, but wasn't sure what exact component was the culprit. Hearing about this problem makes me even more leary of the 5.4 3V and the cam phasers.

The more I hear about what can go wrong, the more nervous I am to take my truck out in the "bush". Let's see, we have cam phasers (sounds like something out of Star Trek), fuel injectors, COPs, plugs that fall apart when removed, a fuel pump driver module that likes to swell up and crack, any number of sensors that can all go belly up at any time, and, an electronic brain that might develop a crack in a solder joint which would render it useless.

Wish I had an old WWII Army Jeep.

- Jack

[Power Hungry]

Jack,

The "electronic brain" issue only seems to be a problem in the 6.0L, and only with specific calibrations. However, the rest of your concerns are entirely valid for your vehicle, although I doubt any would leave you immediately stranded. Most of them develop drivability symptoms over time and give you fair enough warning.

As they say, the more complicated you make it, the more things there are to break.

[BlackSTX]

It all makes me long for the days of the carbs and HEI distributors. No ECMs, no O2 sensors, no injectors, and chips were for consuming with dip while watching sports on TV. Why, I can remember when you could open the hood and actually see all of the engine!