mooseknuckles

I hope someone can help..I have a 86c10 with a lq4/4l80 and after the tranny is warmed up it shifts very hard in every gear...it has always done this, its a PSI Conversions pcm and harness. I have tried switching the ISS and VSS sensors around, checked the trans harness plug, not sure what to look for?...I do not have the wire for the park/neutral ground hooked up to the neutral safety switch because mine only has the single plug for the back up lights.....it keeps throwing this code...

seventy7 caprice

not an expert but i think thats your input speed sensor to the trans, it senses the speed the cranks spinning not the output speed. you need a real time scanner to make sure the sensor is reading correctly or reading at all. my car did the same hard shifting till i had the sensor hooked up correctly.

Old Geezer

iTrader: (3)

- Faulty Transmission Speed Sensor
- Transmission Speed Sensor harness is open or shorted
- Transmission Speed Sensor circuit poor electrical connection

Some check points.............

mooseknuckles

thank you....

mooseknuckles

I got a new input speed sensor...see how that works.

mooseknuckles

got the new sensor in and still throwing the same codes...

ls1nova71

iTrader: (4)

Do a continuity test between the plug and the PCM. Make sure its not open, shorted to ground or shorted to power.

mooseknuckles

tried that I got nothing....

mooseknuckles

maybe this is why....