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Old 31st March 2014, 04:07   #31
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Re: Does downstream O2 sensor affect fueling and FE in Petrol Engines?

Hey guys,bumping up an old thread.
I have bought an air fuel gauge for use in one of my restored cars. Obviously the car in question has no o2 sensors as it runs on a carburetor.
I am planning to fix a non heated o2 sensor(single wire) somewhere in the exhaust system. Will this suffice for me? and is this sort of non heated o2 sensor readily available in India?
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Old 6th April 2016, 20:16   #32
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Re: Does downstream O2 sensor affect fueling and FE in Petrol Engines?

Posting on behalf of some one who needs to get rid of the check light on his car due to cat con damage.

The check light on his Dodge Charger is lit due to cat con damage and in turn the downstream sensor is not sending the correct reading.
The car needs to go on sale before which the CEL needs to be cleared. It can be cleared with the help of a scanner, however it will come up again. The other option was an after market mini cat, but then again it is doubtful if it will help in giving the correct reading the ECU was programmed for.
There is a third option, which is a spacer at the downstream sensor which helps in reading lower post cat con, which again may or may not work.

Are there any other quick options to get rid of the CEL?

Last edited by tharian : 6th April 2016 at 20:22.
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Old 6th April 2016, 22:06   #33
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Does downstream O2 sensor affect fueling and FE in Petrol Engines?

Quote:
Originally Posted by tharian View Post
Posting on behalf of some one who needs to get rid of the check light on his car due to cat con damage.

The check light on his Dodge Charger is lit due to cat con damage and in turn the downstream sensor is not sending the correct reading.
The car needs to go on sale before which the CEL needs to be cleared. It can be cleared with the help of a scanner, however it will come up again. The other option was an after market mini cat, but then again it is doubtful if it will help in giving the correct reading the ECU was programmed for.
There is a third option, which is a spacer at the downstream sensor which helps in reading lower post cat con, which again may or may not work.

Are there any other quick options to get rid of the CEL?

I can come up with at least half a dozen solutions to this problem, ie make the CEL disappear. But the real problem is the broken cat. Fixing anything else but the cat to me appears, to put it delicately, as cheating. It might be even illegal.

So are you asking advise on how you can cheat the potential buyer of this car or am I misreading this?

By the way, technically the downstream sensor is showing the correct value of course. Its is just a value you don't want to see as it sets of the CEL!

Jeroen

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Last edited by Jeroen : 6th April 2016 at 22:08.
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Old 7th April 2016, 06:44   #34
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Re: Does downstream O2 sensor affect fueling and FE in Petrol Engines?

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Originally Posted by Jeroen View Post
I can come up with at least half a dozen solutions to this problem, ie make the CEL disappear. But the real problem is the broken cat. Fixing anything else but the cat to me appears, to put it delicately, as cheating. It might be even illegal.

So are you asking advise on how you can cheat the potential buyer of this car or am I misreading this?

By the way, technically the downstream sensor is showing the correct value of course. Its is just a value you don't want to see as it sets of the CEL!

Jeroen

Jeroen
Like I mentioned in my post, this was for a friend and he wanted suggestions the less expensive way and these were the options he could find . I am well aware of a busted cat con and it's effect, else the mini cat con option wouldn't be listed as an option as well. The original cat con is the last option which would be expensive and he has already spent a bit on overhauling the engine due to bend valves due to the cat con disintegrating.



It would be great if you could share the other options, however only if you feel it is right to do so here.

Last edited by tharian : 7th April 2016 at 06:54.
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Old 7th April 2016, 06:57   #35
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Re: Does downstream O2 sensor affect fueling and FE in Petrol Engines?

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Like I mentioned in my post, this was for a friend and he wanted suggestions the less expensive way and these were the options he could find . I am well aware of a busted cat con and it's effects. And let's not get into going illegal or cheating when there are plenty of us modifying exhaust systems and what not.

It would be great if you could share the other options, however only if you feel it is right to do so here.
If your friend wants to sell the car the cheapest options is to leave it as it is and just be upfront about it.

I dont understand why he would fix it cheaply and then apparently, honestly, trust me, tell the prospective buyer; oh by the way the cat is busted, I made the CEL go away the cheap way.

So I’ll pass on this one.

Jeroen

Last edited by Jeroen : 7th April 2016 at 07:22.
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Old 9th July 2018, 15:37   #36
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Re: Does downstream O2 sensor affect fueling and FE in Petrol Engines?

Knocking on a old thread for some advice! Hope y'all still there xD'

I was looking at my o2 sensor readings and noticed that the values doesn't go as far above the mid-point as it goes below. I have tried taking readings at idle, 1500 and 2500 RPM and the results are fairly similar.

Coincidentally, I am facing low fuel efficiency issues as well. Am I looking at a faulty sensor?

I have added screenshots! Any inputs will be much appreciated
Attached Thumbnails
Does downstream O2 sensor affect fueling and FE in Petrol Engines?-screenshot_20180709143317.jpg  

Does downstream O2 sensor affect fueling and FE in Petrol Engines?-screenshot_20180709143328.jpg  

Does downstream O2 sensor affect fueling and FE in Petrol Engines?-screenshot_20180709143440.jpg  

Does downstream O2 sensor affect fueling and FE in Petrol Engines?-screenshot_20180709143700.jpg  

Does downstream O2 sensor affect fueling and FE in Petrol Engines?-screenshot_20180709143824.jpg  

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Old 24th August 2020, 11:59   #37
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Re: Does downstream O2 sensor affect fueling and FE in Petrol Engines?

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Originally Posted by kifilshah View Post
I have added screenshots! Any inputs will be much appreciated
Which app is this? I suggest you take the readings again with the display in the dial mode instead of graph mode. Somehow I think that readings in the graph mode of display are too lower than actual.

In my case, the graph displayed coolant temperature at in between 77 and 80 degrees while at the same time dial displayed it at 91 degrees.

So, before proceeding for any further investigation, please try this!
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