Oh man, after all this,
i found the right items, have now ordered them,
cancelled the order for the wrong product.

but then……
i noticed this morning……
one of my o2 sensors was unplugged……
really……
smh…….
plug it it, drive to work this morning and fuel economy is better than it has been since i have had the car….
smh…..
guess i will change them anyway

 

Definitely need a titanium sensor as they produce a changing resistance to the O2 content and are supplied by a 5.0 refence voltage from the ECU

The other type generates by itself a voltage from a ground wire

This is where a troubleshooting device ( ELM - _ 327 ) may not see the return to the ECU signal correctly or in range

 

yeah i get all that. Read up on it all now.
for some reason ntk has the wrong part number listed as fitting my car, which caused all this confusion

 

Yes, there is a great deal of misinformation out there on the correct 02 sensors for the X300 I'm afraid.
Been there and survived and as far as I am concerned the correct one is -
Jaguar OEM LHE 1682 AA
NTK (actually original fitment and corresponds to LHE 1682 AA ) - OTD3J-5B1 ( You have got it right )
Bosch - 13789
As usual for Jaguar, a unique part unique part being Titania ( T ) and 12mm thread ( D ), have a browse through the NTK catalogue, there are very view with the OTD part reference, they are predominately OZA.
I have attached relative page from the NTK 2015 catalogue and info on 02 sensors and ECM.
Unfortunately the fact that one of your sensors has been disconnected for some time may have caused the ECM to drop off your 02 sensors functionality and a Oxygen Sensor Orientation may now be required, this unfortunately opens another can of worms for you.

John Herbert
( 1996 XJR )

 

thanks for that.
atleast i know i am not going crazy.
i did not know that NTK was OEM seems odd then that they have bard fitment listings on their site.
oh well.
i have found some goss ones that i showed above that i got at a decent price. Just gotta wait for shipping now.

how would i know if i need the sensor orientation? What would i be looking for?
i am unsure exactly what kind of L/100 i should be expecting.
there are one or two Jag specialists here in sydney that maybe i should get the car out to.

 

In my opinion sense the performance of the sensor changes over usage the ECU relearns over usage / time

So by adding a new sensor the engine may not be optimized on day 1 after installation , but would relearn over usage / time

That being said this would lead to the suggestion to not change all sensors at once

The ECU orientation in the O2 sensor aspect may be to have the ECU match the O2 sensor as it leaves the factory

Your final reading as a tuned fuel mixture system loop would be your short term fuel trim target of 0.0 although + or - 3.0 would not be bad based on the size of the increments of the fuel injector pulse width

You can compare the 3 cylinder bank 1 against bank 2 and watch the effected bank change over usage / time

Finding the equipment to do a orientation would depend on a phone call to the shop

Someone would know more than myself like Andy

 

i will set up my torque app now i have the adapter and see what i get.
maybe your idea of not changing both sensors at once is a good idea. I can see the logic behind it helping the system learn better.
interesting idea.

 

The target of 0.0 STFT should be in all ranges of engine speed and engine load , the load aspect is questionable

This is only valid in the close loop mode or 88 degree C engine coolant temp

 

Wait up here. The 02 reorientation is only needed should the oxygen sensors be installed using the wrong conenctors. Since there are four of them, just do one at a time and you won't mix anything up. The reorientation is there so that if anything gets mixed up, the car can figure out which 02 sensor is which.

 

there only 2 over here fyi

 

Even less useful for you then! You have a 50/50 shot of screwing it up!

 

Just confirming that Australian delivered X300s only have two oxygen sensors down stream from the catalytic converter.
I have replaced them on two X300s

 

so i replaced the O2 sensors, and now economy has gone down to avg of 14.5L/100 for the last few trips to and from work.
watching the instant economy i can see it is higher when the car is cold,
but then gets better as it warms up,
now when i accelerate it doesn't spike as high as it was fuel use while cruising seems only slightly lower, it was always decent enough there. sitting at 3-5L/100 at 80-100km/h
so i think that makes a big difference.

seems like it is running much more like it should.

 

I recently replaced the 02 sensors on my 3.2 after a check with a cheap ELM 327interface and Carscanner app showed the O2s were sluggish and one lagged behind the other.
the old ones were very sooty and marked Lucas NTK Japan so May have been original.

I’d previously struggled to get over 21 Uk mpg but in a 20 mile run from garage home ( having ducked the removal of old ones myself) I was seeing 27 as av mpg.

I used aftermarket ones from British Parts

I’d previously replaced the temperature sensor as a recent replacement was faulty and tripped to -40F after recording the increase on warmup ok through most of the range.

I had also sprayed the MAF sensor wire and cleaned the mesh in front of it.It was not showing a reading on the scanner before the clean and something like 0.4 to 0.8 afterwards. It’s the original 1996 MAF kit.

UK car so no EGR.

Mileage is 114K miles

Car does seem a little slower to pick up on accelerating but maybe it was more eager with excess fuel waiting for more air.

Had struggled to meet MOT 02 figure but now showing 1.02 lambda on same garage emissions test.

 

21 mpg is 13.45L/100 and 27 is 10.46.
jeez that seems crazy low compared to what i would expect.
what kind of driving do you do?

the 3.2 must rally use a lot less fuel than the 4.0L.
i assume it feels sluggish in comparison too?

 

21MPG city is low for a 2 ton car with a 4.0 engine....yikes.
27MPG highway is low too?

I'd love to get those numbers on my car! I have a 4.0 and can't seem to average better than 19 with a city/highway mix.

I have been struggling with a high LTFT that dropped some when I tightened the intake manifold bolts....but I still am showing a LTFT of 7.8. I have a hairline crack in one of the two exhaust manifolds, but both LTFTs are equal.

 

Mostly mixed A roads but the 27 post new sensors was nearly all motorway at about 60mph. Will see how it beds in if there is a learning process for the ECU

The 3.2 is a heavy car and the auto box is only 4 speed. My 05 Merc 320 turbodiesel auto estate daily driver with 118k miles feels slightly more responsive but it’s a 7 speed box.

My previous Jag experiences were with pushrod or 2.4/3.4 XK engines and anything over 20 was good - tho my MK1 2.4 manual was quite economical for the era.

My wife had an 02 320 CLK auto petrol for a while and it would do 32mpg on a run dropping to about 28 on twisty roads.

The X300 seems to warm up quickly but I am aware the gauges are not accurate to stop us enthusiasts worrying. The electric fan/s does/do not cut in until it is hot.

 

i think the way i use high and low is different to how you would.
here as we use L/100.
high numbers = bad fuel economy.
low numbers = good fuel economy.
what i mean is 21mpg looks very good, like using bugger all petrol that i would not think was even possible in my car.
and 27 would be like how is this even possible unless you drive only on highways.....

you say you have combined 19mpg. is that UK or US?
difference would be either 14.9L/100 (UK) or 12.5L/100 US.
if UK then that is similar to where i am atm.
if US then i am nowhere near that. i would like to get that low
14.6 is where my trip comp currently is.

my drive has been ~30min each way to and from work with 15 mins in traffic and 15 mins on the freeway.
so really hard to tell.
i wanna get a chance to take her on a bit of drive and see how she really goes on the open road.
if i take her into the city i know it will jump up maybe to 16L/100. stop start stop start stop start

 

Spud Maat
I have been keeping an eye on my fuel economy 1996 .X300 4Litre sport
Typically around 14 L /100K around town. But I seldom get into inner city driving; more suburban/shopping centre.
As low as 9L/100K on a trip of 380Ks last Saturday Brisbane to Warwick return. Took 35 L to fill up so onboard totaliser is reasonably accurate
Most of the trip was locked onto cruise control.at 100Ks/Hr.
But I think you are on the right track post the O2 sensor changes
Cheers

 

maybe my right foot is a big issue.....
maybe i should accelerate a little softer and see if that changes things.

ignition coils definitely on the list to do just wanna get a little more cash before i spend too much more.