Hi,
This may sound like a retarded question, but I have never delt with this before. How do I find a vacuum leak. I am sure it has one and the truck doesn't seem to have the power it should. I think it may be at least partially from the vacuum leak. I can hear it whistling when I floor it going down the road, but can't find it when I park and look under hood. Thanks for any help!

Here's a retarded answer. I found a vacuum leak in my truck by using transmission fluid and a spray bottle. I just sprayed each line and hook-up and watched for blue smoke. Appalachain-American inginuity.

Sounds good. Where would i look for blue smoke from? the tailpipe?

Spray starter fluid or carb cleaner around vac lines not alot at a time the engine will speed or slow down when u hit the leak it's a lot cleaner to mess with.

vacuum leaks in general are a problem at lower rpms. at wide open throttle the engine has little if any vacuum. a vacuum guage can be a very good dianostic though. what is vac reading at idle? for example an engine with good vac at idle should have a good reading at 2500 if it falls off drop the y-pipe and try again. possible exhaust problem.
what you describe though makes me wonder about the piping between the air cleaner and the eng though i can't hear the noise from here.

Well, I'm not sure about exhaust. I do know that the catalytic converter is new and shouldn't be a problem. I'm going to replace the air filter, but I believe that if this doesn't do the trick, I'm just going to have the engine replaced or rebuilt. The engine seems to have about 120 psi compression (that's with that engine restore additive). Never tried compression without it. It looses a lot of its power when it is revved up and the engine seems to bog down easily. I need more power b/c the only reason I have it is to tow my boat. I feel like I have to turn overdrive off when towing the boat especially if there's a headwind. No power at all. The transmission was rebuilt not long ago (only about 1000 miles on it). Looking strongly at rebuilding it this winter (after christmas) if no solution is found. Biggest thing is that I don't know if it is that the engine is worn out or if there is another problem. No check engine lights. I don't want to replace the engine if it doesn't need it. I'll probably take it to a mechanic, but the ford dealer recommended replacing the engine. It has 169000 miles