Fuel pedal NOT WORKING

[cbarm]

I just put a boost gauge (mechanincal) and also replaced the temp sensor. I fired it up to take it for a spin and now no throttle response at all. This is a '90 with a PSD in it, so not sure if the fuel pedal is original or not. It idles fine, but nothing whatsoever on the pedal...what can I do??

 

[icanfixall]

Thats big trouble there. The throttle peddle is not mechanically connected to anything like our trucks are. Its a large reostat type switch. The more you press down on it the more electrical signal it semnds to the electronic fuel injection. Expensive too...

 

[cbarm]

Hmmm...yea this one is electronic. Would it just all of a sudden quit though or might it give me some signs ahead of time? I drove home, everything was fine. Spent about an hour changing my coolant temp sensor and installing a boost gauge off the MAP sensor line and now there is nothing...

 

[Devon Harley]

either changing or taping the map sensor set off a code that needs to be reset or yes it just stopped working out of no where. Thats the beauty of a psd engine. Sensor's fail with no warning an your stranded.

 

[riotwarrior]

change it all back the way it was....try n see if it works...if so don't fix what isnt broken!

 

[cbarm]

Hmm...could I try giving the MAP sensor a couple taps to see if something mighta got knocked loose of am I totally off my rocker there? The thing is I dont even have the MAP sensor plugged in ATM for better throttle response...

 

[John Deere]

Assuming this is early style powerstroke assembly, it has two plugs on the throttle assy, one is the rheostat plug the other is the idle position switch, basically a on-off switch. If this switch is out of adjustment, it will not come off idle, you will hear it click as you depress the pedal and as you let it back up. To test them functually you will need an ohm meter.

If either of these plugs are unhooked, the engine will only idle.

 

[cbarm]

OK...the "on/off" switch you are refering to is the little button that is pressed by the pedal itself, just below the spring? Good thing I bought a multimeter yesterday...now I can try it out. This should NOT have any resistance, correct?

 

[John Deere]

The on off switch will give you a open and closed circuit result as you push and release the switch, same as holding your two probes apart and then touching them together. Sorry I'm not too good with my electrical terminalogy.

 

[cbarm]

OK...no prob on the terminology...Im pretty bad at the right wording at times. Well hopefully its just that lil button...that should be an easy fix...will check it out in a few mins...

 

[John Deere]

I must more tired than I realized, my spelling is horrid also. Lol

Check pm's

 

[yARIC008]

Have you googled your question? My guess is that the issue of the go pedal not working on the PSD is somewhat common. I know I've read on the new PSD there are three rheostat type deals that way if one fails you are stilll good to go except you get a check engine light. You lose two and I believe you get no throttle response. Not sure if the early PSD where like that or not, my guess is they are the same.

 

[OLDBULL8]

How to check it.

PSD TPS
....It receives a 5 volt reference on the Brown/White ---- ground circuit on the Black/White wire. It also sends a .9 volt to 4.5 volt signal on the Green/White wire to the PCM to indicate throttle position.

The IVS is a normally closed switch. It has 2 wires, 1 is a Brown, a fused battery voltage wire , the other is Red/Orange and goes to the PCM to confirm pedal position. When the pedal is in the idle position the Brown wire at the IVS is battery voltage and the Red/Orange wire is 0 volts.

As pedal travel
increases to approximately 1.3 volts as indicated on the Green/White wire at the AP sensor[or TPS], the voltage on the Red/Orange wire should increase to battery voltage to indicate acceleration.

 

[cbarm]

Wha...?????

 

[War Wagon]

Pedal position sensor failure is somewhat common and you have the symptom.