2000 Ford Focus throttle position

linton · Posted at Sat Jul 04, 2009 5:51 am

Engine Performance problem
2000 Ford Focus Two Wheel Drive Manual 77000 miles

The car drives fine apart from it only ticks over at about 700 rpm, when i loose my foot off the throttle the engine cuts out and shows the warning light, this does not happen if i coast on the clutch. i have been told it is the throttle sensor position??

renaudTN · Posted at Mon Jul 06, 2009 12:14 pm

Could be the TPS indeed. Back probe the wires at the sensor, One is your ground (around 0V), another one is your hot wire (about 5V), and the last one is your signal wire. When you open the throttle, the voltage at the signal wire should go up steadily until 5V (fully open). When you close the throttle, the voltage should drop back down steadily. If it doesn’t go up and down steadily, but rather jump from say 1V to 4 V all of a sudden, that indicates a bad TPS.
You can also disconnect your TPS and put a ohmmeter across your signal and supply wires. As you manually open and close the throttle, the resistance should increase and drop. If you have erratic readings, the sensor is bad.

P.S: I would also check the fuel pressure to make sure there's nothing wrong with that.