Three problems related to engine noise have been reported for the 1998 Ford Expedition. The most recently reported issues are listed below.
The vehicle started to make a noise, when the consumer was driving. The dealer stated the upper camshaft sensor had broken. Then a month later the lower camshaft sensor broke. The manufacture stated the warranty does not apply after mileage has become to high.
The engine makes a pinging noise after vehicle has time to warm up(about 1/2 hr). I've been to three (3) different dealers. The first one said to just put in higher octane gas (it should run on 87 octane according to the owners manual) and that was all they did. They didn't even write it up. The second dealer did the same. The third dealer kept the truck over night and wrote they reprogrammed the computer however this did not solve the problem. I called Ford and they told me they would get in touch with the third dealer and I would be hearing from them soon. It's been over two weeks now and I've had enough. I don't know if I'm polluting the air with this truck or not. It is not suppose to make pinging sounds even though at the third dealership, one of their mechanics told me that all Fords ping. I don't know if this is considered a safety problem or not but I want you to be aware of this because I have spoken to other Expedition owners and quite a few of them are having the same problem. Thanks, al krause.
Windows- all power windows occassionally will not let up if down or down if up. Engine- when stopped, gives an intermitten vibration. Child locks- engages when unlock power locks. Turn signal- if steering wheel not straight, can't engage turn signal. Tires- making sound as if they will peel off at any moment. (tiresize: p255/70r16)( dot number: tire size: p255/70r16 ).