2001 toyota echo During normal operatinng temp. vehicle has a surge at low speed. O2 sensor voltage goes straight to 0 volts maf, tps, and spark adv. voltages all look to be normal. fuel pressure look good plugs are new and no codes. any idea of problem or service bulliten?
Country: United StatesMake: ToyotaModel: echoYear: 2001
Hello and thank you for choosing just answer.
In order to better assist you, I need a little bit more information.
How are you seeing that the o2 sensor drops to 0v? Scan tool or checking the signal wire?
Also you're observing the pre-cat sensor(sensor 1) correct?
And if you have access to a scan tool what are the long and short fuel trims while the voltage from the o2 sensor is 0v? Does the vehicle surge only when the sensor reading drops to 0v? or it surges regardless?
it surger regardless
Hello and thank you for using just answer!What does the long term and short term fuel trim readings register when this is happening?