It seems to be coming up a lot, so here's the test :

5.0 TPS

The TPS is on the bottom of the throttle body; it has 3 wires - red, black and green.
You need a multimeter set to Volts DC. Engine warm. Key on engine off.
(1) Check power feed:
Red lead to the TPS red wire, black lead to battery ground. Should show 4.5 to 5 volts.
(2) Check ground:
Red lead to battery positive, black lead to TPS green wire. Should show battery voltage (11 - 12 volts)
(3) Check signal
Red lead to TPS black wire, black lead to battery negative. Should show about .9 volts w/ throttle closed. As the throttle plates are opened voltage should increase steadily (with no flat spots) up to 4.5 to 5 volts at WOT: then decrease steadily as throttle plates are closed.

You should also repeat the signal test while tapping lightly on the TPS with a screwdriver handle.

If you hit flat spots in the signal test, your TPS is toast.
If you don't have very close to .9 (.97) at closed throttle, notice in the picture that there are 2 screws holding the TPS in position. When these are loosened, the TPS can be rotated slightly to adjust the initial voltage.
When you replace a TPS, you have to "dial it in" this way to get your initial voltage right.
You also want to check that somebody hasn't been messing with the little stop screw on the linkage, people do that, and it messes up the signal; it shouldn't be touching. Binding throttle linkage can cause the same problem.

 

The TPS can test out ok but still be worn out. Should just replace it while the tb is off. And don`t forget a new tb gasket while at the store.

 

Thanks for the advice, but that's not actually off my truck. Just an old t/b I had kicking around, thought I'd take a picture and post the test procedures for anybody who might be having issues and want to test their TPS.

 

What about Ohms testing?

 

Hi chris and great information. I got a new tps sensor and my question is when I install it I just cant put it on Im not to good with electrical stuff. Will I need to adjust it? I just read the other thread were the guys truck wouldnt start and im in the same boat. The only difference is I took the hose off at the throttle body and used starting fluid and my truck starts right up and runs fine but wont start on its. I just took it for rip up the road idles fine drives fine but just wont start. Maybe I should start it and see where the timing is? I think my tps has been bad awhile because it always started but idled up high and then would come down even when it was warm.

 

Sounds like TPS is a possibility. You can get a cheapy voltmeter for like ..$15. Then just test it. No throwing money at things that aren't causing the problem.
If you replace the TPS you need to adjust it with a voltmeter. Can't just throw a new one on.
Are your fuel pumps priming ? You should hear them run for about 2 seconds every time you turn the key off and back on again.
A fuel pressure gauge would be real helpful. When the pump primes, you should be right near max fuel pressure (key on engine off)

 

So if I get nothing on the signal test, the tps is dead? The other tests check out ok.

 

If you have power to it and nothing coming out then TPS is dead.

 

Thanks for the confirmation. It looks brand spanking new. And there doesn't seem to be much room to adjust its orientation.

 

It could very well be a brand new ish cheaper version. This is where a motorcraft replacement would be a good idea.
I know it will seem much more expensive, but if you compare prices and it's 30 dollars or so more for something that will probably last 20 years,as opposed to the knockoffs that typically don't, the extra 30 bucks seems like a good investment. I don't know if it's actually that much more, I'm just guessing, but you get the idea.
I know my truck still has the original motorcraft one 19 years later.