'97 V70 T5 MIL P0120 (TPS) fault

papariccardo · Post by **papariccardo** » 18 Mar 2014, 00:41

I just shelled out $2k+ rebuilding the head on my T5 after overheating, and the MIL came on when first firing. OBD-II scan showed the fault was P0120 - TPS/ Pedal Position Sensor A Circuit Malfunction. The car seems to be driving fine, my son reckon it's slower than before, but I'm not certain. Seems to boost strong in 3rd, maybe a little more laggy than before, but hard to say.

What could be the issue here? I cleared the code, but need to fix the issue.

Post by **Ozark Lee** » 18 Mar 2014, 08:21

I would start at the source of the error code, the throttle position sensor. It is a small black box on the bottom of the throttle body with an electrical connector. Make sure that it is plugged in and, if it is plugged in, unplug it and use some contact cleaner on the contact pins in the connector. Do a visual inspection on the wiring harness that leads to the sensor to make sure that one of the wires didn't get broken or smashed while the head was being being removed and replaced.

The sensor can go bad but the timing is curious for the sensor to fail just as the head was replaced. It can mess up the sensor if it got drowned in carb cleaner while the throttle body was being cleaned.

...Lee