Hi Guys! Just wanted to chat with the experts here at FTE. I have an '01 Expedition with 50,000 mi. I bought it from my pastor who was "religeous" about maintaining it. He decided he needed a Suburban, obviously gas prices don't phase him. Anyway, I purchased the Expy with 28,000 mi on it. It was making a sound that is best described as a leaking manifold. Took it to Ford dealer, they noted the noise and even took time to locate it. Replaced catlytic converter under warrany, not the solution. But they were very nice about it! HA HA Anyway, I took it to my friendly Nissan dealer, they could not find any leaks in the exhuast system. I have lived with the noise for nearly a year now. It has not affected the performance, it just annoying. I am concerned about it causing bigger problems down the road. The bigger issue is that just recently, the Expy has also begun to emit a pinging, sounds a lot like spark knock. The plugs are the originals. I did have an injection cleaning done by the dealer, but that hasn't changed anything. I drive around toen mostly and average between 12 - 13 mpg. The ping is most noticable when cruising on the interstate. When climbing a small grade at 75mph, the pinging is very pronounced. The other noise (ticking) is most noticable when you get to about 43 mph, the car upshifts to overdrive, and you give it enough gas for power but not enough to downshift. It is really loud at that point. Anyway, wanted to find out if you guys knew how to diagnose the ticking or the pinging. Any help would be greatly appreciated.

 

Howdy,
I have a similar noise on my 4.6L 2000 Expy with 55k on it. I get the noise around 70-75 going up a slight grade too, but also at any time when the RPM is low and the engine is under a load, but not quite at the point to downshift. I can almost feel the noise down at my feet when it gets bad...kinda like a piece of semi-dried mud hit the floorboard under the gas pedal. I had my tranny flushed at 37k, and this just started happening about 5k miles ago.
I also have the 43 MPH tick.
I've been advised to have the tranny flushed again, but wondering if it's something like a torque converter gone bad/missing a blade?
Sorry I can't really do anything but share your frustration!!!
-Tim

 

There are a couple TSB's out on the 4.6 and ping issues.

You can read about them at

www.alldata.com