Tps?

[baileyj]

What kind of problems can a bad Throttle Position Sensor cause?, my '02 7.3 PSD will occasionally surge or slow down then return to normal like nothing happened. It'll happen while on cruise or foot and it's not trhowing any codes. Any ideas?

Thanks for any advice and PS, this site is great and informative!!!

[shoit2ya]

I am having the same problem out of my 99! No codes no rhyme or reason....please help, I have already replaced the synchronizer aka., crank pos sensor, didnt help. Could this be excessive water in the fuel?

[jeshoyt]

In the ones I've seen, A bad TPS will cause the SES light to come on, and result in weird throttle respones. My buddy had one go out in his truck. Generally, when he would get on it sometimes the truck would idle and you could push the (fuel pedal) and it wouldn't respond, it would just stay at idle even if you pushed it to the floor. But only for short spurts. Truck also can surge sometimes, or the cruise control can quit working as I recall.. Anyway, they're super easy to change out, took us like 15 minutes or so, but check powerstrokeshop if it ends up being your problem.

[shoit2ya]

The pedal reacts fine, if it starts to "miss" I can throttle up and the prob goes away. Until I am at cruising speed again. Then is starts to "drop out" if you will. Then it will start to "miss" again. I have run about three tanks of fuel through it with the Diesel Power ...911 additive and it makes it a little better. (or it is my mind thinking it is) Then it will act up again. There is NO frequency to the problem, and sometimes it runs perfect. I really appreciate the help and I think this is a WONDERFUL forum.

Chris Cudney

[jeshoyt]

This sounds unlike a TPS problem to me from my knowledge of them. When was the last time you changed/checked the fuel filter?(Tighten it down good and snug. ) Also, what about your oil change situation? Who changed it and how long ago was it changed? I have heard of oil causing similar problems....sort of a wild azz guess but you never know.

[shoit2ya]

I changed the oil and the level is ok. I will check the filter and I also will drop the fuel tank and clean the pressure regulator. There was a secondary fuel tank in this truck that I removed because the valve was bad so I also will by-pass that and see what happens. There are some other posts on here that say to clean the screen on the filter bowl so I am going to see about that as well. This site rocks

[fordnut85]

if your truck does alot of highway driving with the cruise set it is common to have the TPS develop a flat spot and it won't always throw a code but you can test the TPS with a scan tool or an ANALOG multi meter

[shoit2ya]

This happens with the cruise as well as the pedal......I guess I should have said that I am truely sorry

[jeshoyt]

The cruise also? Now it's looking more likely that it is the TPS. If it was me I'd get it scanned to see if it throws a TPS or related code and go from there.

Edit-I see you got it scanned, by the way, TPS are not too expensive if you get them from someone other than the dealer, 10 minute job if all else fails. I hate throwing parts at stuff but it's looking like a good possibility if you can't figure it out.

[fordnut85]

Opps, guess i should have been a little more clear. the problem is the result of using the cruise alot, the throttle stays in the same area for a long period of time with the cruise set wearing that portion of the CPS more than the rest. Then as the TPS sweeps past that point you get a studder or miss, if you let off or accelerate the problem goes away as soon as the TPS is not in the same position. If I had to guess i would agree that it is the TPS but i would throw an analog meter on it or at least a scanner