Probably your valves ticking. They would go faster at higher RPM's and slower at low RPM's. Older vehicles will have loose valves that don't always work as well as they once did and cause a lot of noise. Since it is 1997 model it probably is about time to have a valve job done, which can be expensive, but you can keep driving for a while you just won't get the best efficiency out of your ride.
It sounds like its coming from the motor but sometimes its sounds like its faster than it is at other times
1997 Ford F-150 STD 4WD LB
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Maintenance & Repair
I have a 1997 f150 can a 2001 f150 engine fix that ?
1997 Ford F-150
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Maintenance & Repair
I cannot figure out where this vaccum hose goes. There is nothing to attach it to within the length of the hose, so I think it may have been cut. Any ideas?
1985 Ford F-150 XL Standard Cab SB
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Maintenance & Repair
Is this a vacuum hose problem?
1997 Ford F-150
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Maintenance & Repair
I have found the 1994 F150, and according to the owner, all it is needed is a side window, battery, and an alternator (maybe some tires too, but not sure how the ones that are sitting on the truck now...
1994 Ford F-150 XL LB
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Maintenance & Repair
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