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Discussion Starter #1
Does anybody have any idea what can make all this codes come up? Car runs fine and it has been. But all of a sudden, this morning when I started the car up. Cel popped out and this is what I pulled. No time to diagnose it this morning so I thought I should ask around first before I try to. Thanks guys!

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Looks like the heaters are off line. Either an open ground, or a short to ground ahead of the sensor. It takes two drives cycles to pop. So what did you do to it?

P0031 HO2S heater (RF) circuit low ON 2 O2 sensor heater (See DTC P0031 [AJ]
P0032 HO2S heater (RF) circuit high ON 2 O2 sensor heater (See DTC P0032 [AJ]
P0037 HO2S heater (RR) circuit low ON 2 O2 sensor heater (See DTC P0037 [AJ]
P0038 HO2S heater (RR) circuit high ON 2 O2 sensor heater (See DTC P0038 [AJ]

P0051 HO2S heater (LF) circuit low ON 2 O2 sensor heater (See DTC P0051 [AJ]
P0052 HO2S heater (LF) circuit high ON 2 O2 sensor heater (See DTC P0052 [AJ]
P0057 HO2S heater (LR) circuit low ON 2 O2 sensor heater (See DTC P0057 [AJ]
P0058 HO2S heater (LR) circuit high ON 2 O2 sensor heater (See DTC P0058 [AJ]
 

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Discussion Starter #3
Looks like the heaters are off line. Either an open ground, or a short to ground ahead of the sensor. It takes two drives cycles to pop. So what did you do to it?

P0031 HO2S heater (RF) circuit low ON 2 O2 sensor heater (See DTC P0031 [AJ]
P0032 HO2S heater (RF) circuit high ON 2 O2 sensor heater (See DTC P0032 [AJ]
P0037 HO2S heater (RR) circuit low ON 2 O2 sensor heater (See DTC P0037 [AJ]
P0038 HO2S heater (RR) circuit high ON 2 O2 sensor heater (See DTC P0038 [AJ]

P0051 HO2S heater (LF) circuit low ON 2 O2 sensor heater (See DTC P0051 [AJ]
P0052 HO2S heater (LF) circuit high ON 2 O2 sensor heater (See DTC P0052 [AJ]
P0057 HO2S heater (LR) circuit low ON 2 O2 sensor heater (See DTC P0057 [AJ]
P0058 HO2S heater (LR) circuit high ON 2 O2 sensor heater (See DTC P0058 [AJ]
Yeah, it kind of freaking me out that all of my sensors heater went out like that, or at least it seems that it is. I havent done anything to it yet, I havent even looked. Just trying to get an idea first. And if your talking about mods, the only thing I did was put an o2 spacer to fix my po421/31, but that was about a year and a half ago. other mod was big tb this past summer. Can it be related to the cold weather?

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Check the ETC relay. See post # 41 of my sig. Power is from IG1. Your gonna have to look as they are all tied together. Same power feeds the coils and your still running so ohm out from one side of the ign coils to pins C D of the O2 connectors. I bet that side is OK so its the other side. Do keep in mind that most of that stuff goes straight to the ECM so play nice.
 

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Discussion Starter #6
UPDATE: so I started the car this morning and it was fine. No funny sounds or anything. After I warmed it, I drove of and it drove fine until I came to stop. Everytime I pressed on the break pedal to stop, my rpm goes up and down like it was going to die then revs up (same symptom when I had a vac leak). So I went back home and started looking around. I checked all the o2 sensors, relays, ignition coils and spark plugs and everything was fine. I knew that it couldnt have been the 02 sensors since its not realistic for all 4 of them to go out at the same time but I checked anyway. Cleaned all the connectors, blew smokes on all the vac line and nothing. Still the same codes and messed up rpm. So I resorted to the idea that maybe its weather related. So I removed my cai and intalled my sri and boom, Everything is back to normal. No codes and messed up rpm. I turned it off and started it a couple of times and no codes, test drove it and no codes so I think Its all good now. I forgot to mention that I have no cats at all, I had it deleted a couple of years back. Just sharing my experience for the future members that might have the same issues. I red on 6 crew that this codes only come up when you delete your cats.

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So are the downstream sensors plugged into sims?
In normal use, the heaters only help them get on-line faster. O2 senors are TWO PARTS in one. Heater and Sensor. When the sensor is cold it can't accurately read oxygen concentration (O2). The upstream O2 rely on exhaust AND electricity to heat them to temp. With cats, the downstream sensors are heated by the cat's effectiveness so they come up to temp pretty quick without a heater.

In your case, the cold weather would play a role on warm up time but it should have been greater issue for them if bunged deep by plug foulers. Not simulators. Details seem to matter.
 

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Discussion Starter #8 (Edited)
So are the downstream sensors plugged into sims?
In normal use, the heaters only help them get on-line faster. O2 senors are TWO PARTS in one. Heater and Sensor. When the sensor is cold it can't accurately read oxygen concentration (O2). The upstream O2 rely on exhaust AND electricity to heat them to temp. With cats, the downstream sensors are heated by the cat's effectiveness so they come up to temp pretty quick without a heater.

In your case, the cold weather would play a role on warm up time but it should have been greater issue for them if bunged deep by plug foulers. Not simulators. Details seem to matter.
Yeah I got a spacer, I put that to get rid of the po421/31 and it worked on my 6. I mentioned it to you on my 1st reply to your answer. Thanks for the details man! Oh an I dont have sims, just a spacer because theyre cheaper. Lol..

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Hello, i have a 2004 mazda 6s V6 and i have had the exact same 4 codes consistently on my car for several months now. My car runs just fine. Everything works (air conditioner, heater works great, never has overheated at all) but now i have to smog it to get my new 2020 tags and as long as that check engine light is on, its not gonna pass smog. What do i need to do first? What checks or where do i even begin. All four sensors are functioning cause i ran live data stream from my code reader. But not sure where they should be reading at. The numbers seem to be jumping around a lot.
 
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