Problem Description and Possible Solution
The Throttle Position Sensor can get out of adjustment due to wear in the throttle body or due to carbon build up. This will cause the idle timing to advance more than 30 degrees which will cause very high HC and NOx emissions. Conversely, the Throttle Position Sensors can wear out and not properly advance the timing which causes a lack of power and poor fuel economy.
Average mileage: 191,600 (131,000–225,000)
16 people reported this problem
One day I was coming off the freeway after driving 20 miles and it died at the stop light. Started it back up. Died again. My problem was low idle about 300 RPM. No check engine light on. My buddy jumped the ECU and pulled the code for a IPS. I changed the IPS no difference in idle. So I returned the $100 sensor put the old back on. I pinched off a vacuum line that goes to a plunger that pushes idle down right above the IPS. That brought the idle up a bit. Just enough not to hit my 4 runner with a bat. Cuz of it stalling all the time.
A month goes by and I still can't figure it out. I put seafoam in a vacuum line off vacuum booster. It smoked terrible ran like manure. But now a check engine light is on.
Now it's been a two months. I drove it on a long trip and it still ran bad the hole trip. In till I got back home then it started to run pretty good. Off and on it seems to plug up or foul out plugs.
Anything you can tell me would help.