22 Throttle Position (TP) sensor circuit (signal voltage low)

1970z28
12-21-2006, 08:21 PM
can someone tell me what i need to do to fix this on my 94 lt1 street car. it also has a tune from madwolf and he set the idle to 850 but it want idle down to that, stays around 1500 to 2000 rpm. it done this before i sent him the computer and shifts real hard at 1-2 shift @25 mph then 3-4 shift @40 mph and will not go into od. until 55 mph. also thanks to andrew@ akm cables on the repair of a cable from one of there competetors to help get me going.

Injuneer
12-22-2006, 11:34 AM
The code sets when the closed throttle TPS voltage is below 0.20V. You need to test the operation of the TPS, meauring the voltage between the blue wire and the black wire with the throttle closed (0.20-0.90V), rotate the throttle open slowly watching for a smooth voltage increase, and then at full throttle, should read about 4.0V higher than the closed throttle position. Also check to make sure you are getting 5.0V between the gray wire and the black wire at all times (key on).

You need to find out why the voltage is so low at closed throttle. Could be a faulty sensor, may need adjustment ifs its on an aftermarket throttle body.

1970z28
12-22-2006, 08:15 PM
thank you will check tomorrow.

1970z28
12-23-2006, 12:50 PM
only getting 0.03 v at throttle closed. voltage will not increase when i open the throttle up, between blue and black wire. getting 5.0 v between the gray and black wire. any idea bad sensor it has the stock throttle body

1970z28
12-23-2006, 04:02 PM
fixed it, removed the sensor and tried to ohm it out but nothing would happen. went and bought one works perfectly.