HELP~ My 2002 Expedition, 5.4L, Triton V8, Eddie Bauer, is making a terrible loud knocking sound. Note that my car is running great. Just knocking terribly......
At first I noticed it when it was starting, but now it does it sporatically while driving. Typically it happens right before it shifts around 2,000 RPMs~ sometimes it knocks when I am driving and take my foot OFF the accelerator.
At first we thought it was a spark plug that had come loose or a bad coil, but my husband checked those and said they were fine. Our mechanic said it could be a lot of things, but more than likely a crankshaft bearing gone bad. We hooked up a hose and listened to ivarious parts of the engine. the noise can be heard through the oil pan. Not super loud, almost an echo......
RIGHT BEFORE this noise started my husband installed a new alternator and gave it an oil change. He also checked the plugs, but did not change them. I thought they should have been changed because they looked whiteish, but he said they were fine. (He is hesitant to change them out because of the spark plugs being blown problem we had a few years ago caused by the bad threads and we had to have a heli-coil or something done.) Also, husband says that the hole or brass plate where the iginition coil goes was stripped and the screw wouldn't hold. So he put threadsaver stuff to try and hold it......
It was right after the alternator that the car started making the noise upon starting..... at my request he changed the belt, but the noise didn't go away. In fact, it has just continued to become more frequent and worsen. We are hoping it is just a crankshaft bearing and not a rod.... if it is a rod, would my car be running this great?
Any mechanical input is appreciated.
At first I noticed it when it was starting, but now it does it sporatically while driving. Typically it happens right before it shifts around 2,000 RPMs~ sometimes it knocks when I am driving and take my foot OFF the accelerator.
At first we thought it was a spark plug that had come loose or a bad coil, but my husband checked those and said they were fine. Our mechanic said it could be a lot of things, but more than likely a crankshaft bearing gone bad. We hooked up a hose and listened to ivarious parts of the engine. the noise can be heard through the oil pan. Not super loud, almost an echo......
RIGHT BEFORE this noise started my husband installed a new alternator and gave it an oil change. He also checked the plugs, but did not change them. I thought they should have been changed because they looked whiteish, but he said they were fine. (He is hesitant to change them out because of the spark plugs being blown problem we had a few years ago caused by the bad threads and we had to have a heli-coil or something done.) Also, husband says that the hole or brass plate where the iginition coil goes was stripped and the screw wouldn't hold. So he put threadsaver stuff to try and hold it......
It was right after the alternator that the car started making the noise upon starting..... at my request he changed the belt, but the noise didn't go away. In fact, it has just continued to become more frequent and worsen. We are hoping it is just a crankshaft bearing and not a rod.... if it is a rod, would my car be running this great?
Any mechanical input is appreciated.