D1 O2 sensors?

terryjm1

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Jan 23, 2011
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Just yesterday I installed new catalytic converters on my 96 D1. My exhaust is still stinky and it looks like the downstream O2 sensors are newer than the upstream. I’d rather not have the thing running rich.

I know there are different types of O2 sensors and the wrong ones will cause rich running but not trigger a code.

Pricing for replacements is all over the place whether from Land Rover vendors or others. Here is one I found on Amazon.

Is this the right one and is this a reasonable price. I’d prefer to not replace all 4. Is upstream or downstream more likely the problem for rich running?

Any other suggestiones?


87094B5B-FFBB-4EFF-B9A2-4A42BE84098C.png
 
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terryjm1

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Jan 23, 2011
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Here is what LR Direct is selling.

Do you think Intermotor is the correct one?


1E323F3D-8369-46EB-A6A3-52B85980CEB2.png
 

terryjm1

Well-known member
Jan 23, 2011
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Probably should have waited a little longer to post about this. I just took it for a drive and got an immediate check engine light for “Coolant temperature sensor out of range” code. See the photo below for the temperature it was transmitting. Considering it has never been negative 40 here and was about 60 degrees when the code popped, I suspect I need a new coolant temperature sensor. It took about 5 miles to come off -40 and then went to where it should be at 180.

I still think I may need O2 sensors but I will wait a bit. 7CA87344-0E9C-423A-829E-E5DCAF53B50E.jpeg
 
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terryjm1

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Jan 23, 2011
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ntk 25044 @ Walmart

This is what I installed. NTK 25044 They work pretty well. Amazzn used to have them. no longer it seems
Do you use these with a non-AEL? Mine is a 96 without AEL. The upstream ones have Lucas part number so I will assume they are original. I think I am just going to replace all 4.
 

p m

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Is upstream or downstream more likely the problem for rich running?
Terry,

you'll do well if you read some on GEMS. Downstream O2 sensors are only used to control fuel mixture if upstream sensors completely failed; otherwise, they are there just to monitor the state of catalytic converters.
To answer your question directly - upstream.

Coolant temperature sensor can cause overfueling, but if it is stuck at -40C, ECU will learn about it and substitute a mostly-wrong but more-common value.
 

terryjm1

Well-known member
Jan 23, 2011
1,486
375
Terry,

you'll do well if you read some on GEMS. Downstream O2 sensors are only used to control fuel mixture if upstream sensors completely failed; otherwise, they are there just to monitor the state of catalytic converters.
To answer your question directly - upstream.

Coolant temperature sensor can cause overfueling, but if it is stuck at -40C, ECU will learn about it and substitute a mostly-wrong but more-common value.
Thank you, very helpful information.
 

terryjm1

Well-known member
Jan 23, 2011
1,486
375
I went ahead and ordered 2 sensors to replace the upstream sensors and a new coolant temperature sensor. I will report back how it all works out. I also have a set of new injectors I will probably install. All parts are original and after 155,000 miles it’s time. I monitored operation of the O2 sensors for a while yesterday. One would seem to be working fine for a while and then just drop to all zeros and stay there. I didn’t notice this previously as I didn’t watch long enough.
 

terryjm1

Well-known member
Jan 23, 2011
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I replaced the coolant temp sensor, upstream o2 sensors ((LRDirect sourced), fuel injectors (4 hole type “upgraded”) and while I could get to them easily, the rocker cover gaskets. Wow, the inside of the rocker covers and intake plenum dirty. Surprisingly, the top of the heads and valve train were relatively clean.

All issues have resolved. Now that all things that propel it seem to be in order it is time to go through the brakes and suspension.
 

terryjm1

Well-known member
Jan 23, 2011
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375
I was able to confirm the Intermotor boxed sensors sold by LR Direct are Titania. They were also the lowest priced of those I found available.5A50E019-BC7D-4C74-9307-60FB8BA1CFB7.jpeg
 
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