At idle some times my idle will jerk up and down 100-300 rpms. It never dies or anything but will do this. I figured it is my TPS. How do I go about cleaning/checking my TPS voltage? It is a 2.9L engine. I am pretty sure where the TPS is, one time I think I unplugged it by accident and it would not idle, but stay running I if kept hitting the gas (is this the TPS?). It is located near the intake manifold running towards the throttle body. Also should my TPS voltage be around .995?

 

ttt, pleas help I need to know asap before tommorow morning!

 

ttt!

 

A couple of things can cause the surging idle you descibed. First clean the inside of the thottle body(if you haven't already done this) sludge inside the throttle body can cause this. If this don't seem to help then it might possibly be a TPS problem, most likely the TPS connector, not the sensor . Ford has had problems with the wires coroding in the connector. To repair this, pull the weather pac out on the backside of the connector , clean the wires & resolder them to the terminals. BTW, TPS voltage at idle is .5-1 volt. Hope this helps!

 

My TB is clean as hell. I took my DMM to my TPS connector and it read above 1v . How do I go about adjusting the voltage? BTW it does not do this often, it is rare but will be it on accasions.

 

Make sure you're reading the signal return voltage, not the reference voltage(which is 5 volts). If the signal return voltage is over 1 volt make sure no one has turned the base idle stop screw in to trying to adjust the idle. If this has not been tampered with ,then the TP sensor will have to be replaced. They are not adjustable on the 2.9. Good luck!