My car hesitates to start and whwn it finally doea it runs very rough and sputters til i give it a few pumps on the gas peddle then she begins to run smoother. I checked with obd2 and got code p0135. So i replaced both upstream and downstream o2 sensors and the continues.. i need to smog my car but even after clearing the check engine light it comes right back on. I dont know what else i should check. Can u please help?
My car has 350000 miles.
My car has an automatic transmission.
Hi There, I would suggest looking to other possibilities that may contribute to the O2 sensor producing a bad reading such as a failing mass air flow sensor (causing too much fuel to be introduced to the motor), bad fuel injectors or a clogged catalytic converter. When the O2 sensor is not working properly, this will cause false readings to be relayed to the computer causing inaccurate adjustments to be made to the intake and fuel system in your engine. I would suggest having an expert from Your Mechanic come to your home to diagnose your emissions system.
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