I've searched back through a year of posts on this forum researching a very light pinging type sound I get from my 5.4L during acceleration (especially in 3rd, 4th, and OD). Once at a constant speed on level, the pinging type sound goes away, but if you press on the gas some more, you'll hear it again..
Performance is great, gas mileage is as expected (15.5mpg average), and the engine pulls smoothly. But, I prefer my engines noises to be heard from the tailpipe and not from the engine compartment..
Dondo7 according to posts several months old has not had much luck with dealers admitting there is even a problem..
I have a Y2K F250 XLT SC 5.4L 5sp, 4.10LS, only 2300 miles on it so far, so I'm well within warranty..

I guess if this is something that all 5.4L's do then then its ok, but if only a small % of 5.4L's do this, then I'll be concerned..

At best, the pinging will affect resale value What do I tell folks years from now who testdrive the truck when I'm trying to sell it?,
"Thats a normal sound these engines make"..
They'd believe that, NOT..

 

Dondo7, I just saw that your engine got diag'd as piston slap and they're replacing your engine..
Did you really have piston slap symptoms (knocking at cold startup idle), or did your dealer just say it was piston slap so they could get a new engine..
I know that you had the 'pinging' problem too.

It's unlikely that my engine will develop true piston slap as the truck was built 10/28/99.

 

R Bess, I am having the same problem with a 1998, auto, 5.4L F-150 XLT. It pings when you step on the gas, while loading it down a little before it has a chance to downshift. even more when you place the automatic transmission into second gear, and start from a stop and feel out the power band where it likes to ping the most. It is not nearly as bad when you run 93 octane gas.

I plan on taking the truck back to ford again for a second time for the same problem, and tell them to fix it, because the next (third) time I'm back the lemon laws take effect. I do not have any desire to burn expensive 93 octane fuel for the rest of this trucks life. My guess is they could program the PCM (Power Control Module) with a more low octane fuel friendly program. My service rep. gave nice yes answers but could not tell me what they did to the program in order to make the ping go away. So guess what I'm back again with the same problem. Makes you feel like they don't know what is going on. I would rather that they let me talk to the mechanic than the service rep. At least they could cut out the middle man confusion.




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Hey guy just reading your post about a light pinging sound. My 5.4 with 350 miles has the same sound, what I'm hearing is a light spark knock. Ford is trying to make these big engines run on regular gas by retarding the spark advance to reduce emmissions. Try running some 89 octane in your truck and see if that helps, it should. I talked to the service manager at the local dealer who I've know for years and he dose'nt recommend 93 at all under no circumstance. These engines could vapor lock with 93 under warm conditions. Have a great day and may the good Lord take a liken to Ya!

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kingwc 2000 XLT F150 5.4, 3.55 LS, Chestnut better everyday.

 

R Bess-
Yes, mine developed the classic cold start slap which was unmistakable.

I never could get to the bottom of the ping problem. Different grades/brands of gas did not help. One of the service Depts I spoke too about the problem reported the issue to Ford Engineering as they (the dealer) didn't have a clue what was causing it or how to fix it

My new REMANUFACTURED motor is not pinging. I guess that's about the only bright spot in my life...

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99 F150 5.4 4x4 ORP 3.73 styleside deep wedgewood blue ..no mods (yet)