My check engine light goes on and off. My scan gauge will read multiple codes usually around 27-28, the first one that appears shows to be something with the catalytic converter. My gas mileage drops by .1 nearly everyday. Any suggestions on what it could be?
What software version do you have? I believe ScanGauge had an issue with the rolling codes on earlier versions.
Assuming you are reading the scan guage right http://www.carparts.com/details/Toyota/Prius/Eastern/Catalytic_Converter/2004/EAST40712.html?TID=gglpla&origin=pla&gclid=CjwKEAiAm8nCBRD7xLj-2aWFyz8SJAAQNalaZqI7GCktPuNUrafDfgFfdsm6gLgyOumLCvRCIpQQbhoCixPw_wcB&gclsrc=aw.ds
Most likely you need a new catalytic converter. When they go bad, your check engine light will stay on and off.....until finally it stays on forever
Do you have any x-gauges programmed on your scangauge? My Scangauge gives false codes if I have any x-gauges displayed. But if I just turn all 4 gages to standard gauges it displays correctly.
If you are interested go to LinearLogic online and send them an email for instructions of how to return for software upgrade. They have a really quick turnaround.
Alright, so I removed th xguage codes and am now only getting th P0420 code. How can I determine this is for sure the cat and not the air fuel ratio sensor? If it is the cat how difficult would that be replacing on my own?
It really can only be the rear o2 sensor or catalytic converter. Front sensor is the one that’s air fuel ratio sensor. Catalytic converter is the way more likely option. How much oil does your Prius consume? How many miles has it got? To be sure you need to watch life data from the front air fuel ratio sensor and rear oxygen sensor and then figure it out based on those. But catalytic converter is way more likely especially if you got more miles and/or it consumes some oil. Catalytic converter is pretty simple to replace. If you have weld in catalytic converter it of course needs to be welded in and if it’s original type then you only have couple of rusted bolts to deal with. And those exhaust sensors.
It's got about 142,xxx miles on it and consumes about a quart of oil every 900-1000 miles. I'll get under it today and check it out. Now I know this is illegal and not good for the environment, but in the meantime, until I can afford a new cat would it be best to remove the cat and just run a straight pipe?