i’ve checked my ecu and it’s throwing out codes for my fuel supply system and my EGR system. I was told that most likely my o2 sensor is bad and that if I replace it, my car should run fine. i wanna know if having the bad o2 sensor in my car is affecting performance. I went to the auto shop to buy a replacement and the guy helping me asked what was going on and i told him that the ecu was reading that I have a bad o2 sensor. he then proceeded to tell me that it may just be my ecu throwing out an old code, but i told him i reset the ecu and was still getting the same thing.
now i’m not so sure if i rest the ecu properly. I don’t have the 7.5A back up fuse so i took out the 10A ecu fuse instead for about 10 min.(got preoccupied), put it back in and turned on my car. My car was already at running temp. so i didn’t leave it running for more than a couple of minutes, did i do this wrong??? if not and i need to replace the sensor, is $63(original part, not universal) worth it or is it ok to run on a bad sensor???
one more question, should i just get the o2 sensor or also get an egr valve since the other code is about the egr system??
When I reset my ecu i just unhook the negative battery cable for a few mins. It is best to do this when the car is cold. That way when you start it up it will reprogram itself for a cold start up. Just start it up and let it idle till the tach drops to around 750 then take it for a drive. Do all types of driving, slow, fast and in between. My first guess to your problem would be an O2 sensor. Second would be that your cat is clogging up.
could it be my o2 sensor that makes my car’s revs to fluctuate while it’s in park or neutral??? i had an extra one lying around and decided to install it and see if there would be a difference and there is. With my old one installed, the car would fluctuate revs when it was cold, but with this other one installed, it fluctuates revs no matter what.
is it the 02 sensor or could it be something else??? i had my car up on jack stands for the past week so maybe it could be something else??? i dunno. my car’s automatic, maybe the tranny fluid isn’t getting to all the places it should be.
when the car is cold there is a cold idle valve that regulates the idle. This can get dirty and need cleaning. it is located on the intake. Its technical name is something like IAC sensor or something like that.