97 5.0 won't rev and dies. plz help

[4noMore]

hey guys first read bare with me I have a 97 Ford Explorer 5.0 it refuses to rev past 3500 rpms when in drive it seems like it just loads up and will not go any more. if the truck has less than a 1/4 tank of gas and it is on a slight decline(facing downhill) it takes forever to start it will crank and crank and crank before finally sputters and runs.if truck is on flat ground or has more than quarter tank it starts every time no problem. so far I have eliminated the catalytic converters they are not plugged, I have unplugged the mass airflow sensor with no change and I have changed the spark plugs. the computer is not throwing any codes stored or otherwise the only thing I have been able to figure out is that when the truck is acting up and a scanner is on it at the same time both o2 sensors were zeroed. however when the truck is running fine o2 sensors are working fine I have also replaced the computer still no difference. the truck has 170,000 miles I Drive it everyday its just getting to be very annoying and I cannot figure it out. Please help. THANK YOU.

 

[4noMore]

I forgot to mention occasionally if I take a corner too fast and it is below a quarter tank it will die also if it is below a quarter tank and I'm facing downhill at the stop light or stop sign it will sputter and die.

 

[Dave 1955]

But it still wont rev up much with a full tank..or does it?

 

[1998Exp]

The no-start with little fuel in the tank when facing downhill is a known problem, common to all Explorers of that vintage - something to do with the geometry of the tank and the location of the pump inside it. Nothing you can do about it, except not letting it drop below a couple gallons.

I forgot to mention occasionally if I take a corner too fast and it is below a quarter tank it will die also if it is below a quarter tank and I'm facing downhill at the stop light or stop sign it will sputter and die.

 

[4noMore]

anything above 1/4 tank seems to work fine however I also notice when it's 80 degrees or above it gets very picky as I'm driving down the road it will start to hesitate and sputter my throttle will disappear and it'll Idol at about 600 rpms real choppy to the point where it dies after I shut it off and let it sit for about 10 minutes then it might run good for another 10/15/20 minutes. And when it starts to act up I have no throttle meaning it won't accelerate at all or sometimes I can get it to move a little at very little throttle.

 

[jremington59]

Have you checked the fuel pressure?

 

[4noMore]

Not yet but its not a constant thing. So I would have to check while its doing right?

 

[Green68]

Tps

anything above 1/4 tank seems to work fine however I also notice when it's 80 degrees or above it gets very picky as I'm driving down the road it will start to hesitate and sputter my throttle will disappear and it'll Idol at about 600 rpms real choppy to the point where it dies after I shut it off and let it sit for about 10 minutes then it might run good for another 10/15/20 minutes. And when it starts to act up I have no throttle meaning it won't accelerate at all or sometimes I can get it to move a little at very little throttle.

Check your "Throttle Position Sensor". I had one do the exact same thing on a Mercury with a 5.0. I put a volt meter on the lead going out to the computer and could see the voltage dip when it hesitated. It's easy to replace.

 

[4noMore]

The one thats on it is new about 1.5 years ago but I will check it. When its activities g up because of the heat it will also only rev up so high traffic n neutral as well.