What about da-vina interface ? Will that work on X300 ?

 

Same advice as Mongoose. Buy a Chinese clone and it will probably work, but who knows for how long.

The DA-VINA is a J2534 pass through device meant to connect the cars OBD2 port to some kind of computer. Whether it's DA-VINA or Mongoose, it does the same thing.

I see you're in Finland. I can understand why you probably don't want to take it into a shop and control your own destiny.

Ideally if you could get your hands on a Genrad GDS 500
Or 510, you'd be good to go.

If you browse through the General tab, you'll find much more information on WDS/IDS. I will warn you, you'll end up reading through hundreds of posts, but you'll learn a lot. Lots of helpful and knowledgeable people there. I was able to bring an old original WDS machine back to life!

 

Can Genrad be used adapt O2 sensors and TPS ?

 

I found with mine the TPS was set at 0.63 volts and had no available adjustment to it . My TB is clean from interference from hitting the stop . By drilling up a size to a larger set of mounting holes I was able to get my 0.601 . Depending on whether my TPS was ever replaced the ECU was probably never reoriented to tell it where to new 0 % throttle was . So the engine regulation was lost from there . You might take a look at this and if you get your TPS in range you may not need a reorientaion to tell it where the 0 is . Besides it would be a good idea to be in range for the future if you were to change out the TPS and not have the ECU biased out of whack . I was able to tap into the wire to read this voltage as it goes across the fuel rail channel . You can cheat and read the resistance at the ECU connector as well because the TPS is just a simple variable resistor with a sweeping wiper arm . The TPS may not have anything to do with your engine regulation issues today but If you were to spend the effort and money for a reorientation at least you TPS will be square and not biased .

 

My throttle position is 12.2% when car is at idle. and 80% At WOT when read through OBD. The actual and relative values are same.
If I calculate analog input voltage from those idle is 0.61V and WOT is 4V if input voltage is 5V
I haven't yet measured the actual voltage from TPS.
Would that kind of values affect car not going to closed loop ?

 

The values I read at 0.601 volts at Idle is 2235 ohms and at 0.63 is 2325 , seams backwards intuitively . Read from red 11 through red 12 . Taking into consideration of installed throttle linkage tension pulling off the stop there was none . Just double checked today and at 0.597 volts it is 2207 ohms . The voltage is read from the Green/Yellow wire . Figured it out , I'm reading the dead side of the wiper and not the live side . Have you backed your linkage off from possibly being to tight ?

 

You may have a problem with O2 sensor wiring. Have a look at this thread and carry out some of the tests suggested (jump to page 2 and 3).

https://www.jaguarforums.com/forum/x...-175014/page2/


ELM 327 based scanners have a problem correctly reporting O2 sensor voltage on the X300 (which has a Titania sensor and should be between 0.1v - Rich and 4,7v - Lean) so don't rely too much on your Torque readings. Get some actual voltage readings from the sensor connector.

 

The Titanium sensors on the X300 generate a resistance that the 5.0 volt reference from the ECU gets returned as a modified voltage . The other type generate a voltage from within from a grounded end through to the ECU . This makes a difference in the PID chosen in the ELM327 ( ? ) I never could get mine to read only output STFT

 

I measured the lambda sensors at connector at engine bay

1. The resistance between blue/purple wire and engine block 0.5-1 ohm

2. The voltage between lambda sensor wire and corresponding ground wire (blue/purple) when ignition on, but engine not running 4.7V on first 5.0V on second

3. Voltage between same wires when engine is idling 0.1-0.3V

4. Voltage on those wires when throttle is pushed and released quickly 3.5v-4.0V going quickly back to idle values 0.1-0.3V. Lean condition is probably caused by fuel cut when throttle is closed.

I also measured voltage between MAF signal wires at connector and it gave result of 1.3V at idle

I also noticed something at Torque app




Is this the reason or result for open loop ?

Also on AJ16 engine in euro configuration has two lambda sensors AFTER downpipe cats. Wouldn't the cat efficiency affect lambda reading and cause incorrect fueling ?

 

With an external meter The O2 sensors seem to be responding correctly . Have you checked the condition of the ECU connectors for corrosion and socket to pin bite or grip ( sockets actually 2 tags that can be spread ) . History of ECU connector corrosion . Sockets require a 2 prong release tool as a single will damage them . Socket pin out numbers coming up . Clean Shield grounds ( PIG153L located upper left firewall multiwire terminal ) ?

Red 16 B1S2 return signal to ECU

Red 18 B2S2

Red 6 B1S1

Red 19 B2S1

Red 8 reference 5.0 volts spliced to all 4 sensors

From my understanding and I can be wrong the trim is controlled by the forward O2 sensors and the aft is for code 420,430 Cat efficiency verification .

Cracked exhaust manifolds or leaking donut gasket ? Can make the STFT rich

EDITING

 

Thanks I'll check the ecu pins next.

Euro version of AJ16 only have 2 lambda sensors and they are after first pair of cats.

I have just changed the manifolds because they were cracked and I luckily found one set of non cracked ones from ebay.

 

US has 4 Cats and 4 O2 sensors . You can damage the donut gasket metal flange on the downpipe and can be seen as you are rich some black smoke coming out , Saw this with mine . If your lucky you might retorque the downpipe bolts as you apply grease to the theads to get a better seal before removing and inspecting . New engine block and donut gaskets when last worked on ?

 

I changed all the gaskets when I changed the manifolds and I also used exhaust mounting paste on all connections.

Back to my question if the lambda sensors which adjust fueling are after cats, wouldn't the cat efficiency affect lambda reading ?
Lambda sensor measures "surplus" oxygen in exhaust gas and catalyst uses oxygen to "burn" Nox to N2, CO to CO2 and HC to H2O.
So if catalyst is not working as efficiently as it should (not using as much oxygen as it should) lambda sees too much oxygen in exhaust gas and tries to make mixture richer ?

Or is all the oxygen needed in before mentioned process released when Nox is converted to N2

 

Makes since for a 2 sensor , There is a process to leach or clean the cats with Oxylic Acid but if you go to far is will leach the Platinum alloys from the ceramic substrate .

 

I asked this because I have removed the down pipe cats by using the no catalyst model down pipe.
I welded bungs on those down pipes where I mounted the lambdas.
Even if that affects the fueling it doesn't explain why the car doesn't go to closed loop.
Since I got the car I have wondered why are the oxygen sensor mounted after cats as all other cars I have seen the oxygen sensors are always before cats ?

 

The 4 O2 sensors are Fwd and Aft of the Fwd Cat in the US . If you put the sensors Fwd of the Fwd Cat and your ECU mapping is programmed for Aft as factory configuration ( ? ) might explain the high Lambda and open or closed loop .

 

But if the catalysator efficiency affects engine fueling how Jaguar ECU manages degrading catalysator ? It can't do that with fuel trims as it doesn't know that extra oxygen is because of badly working catalysator ?

 

I can be backwards and confused and the factory Jaguar X300 configuration for rest of world is where ? Where on the pic is your modified installation .

 

From bitter expensive past experience, I'd recommend trying a different ecu.
My XJR has Andy's reprogrammed EPROMs so I gently swapped these over to a different secondhand ECU and now it runs in closed loop once warmed up.

 

I used the part number 1 from picture




It's otherwise direct fit I only had to drill holes and weld bungs for oxygen sensors. I mounted sensors approximately same position as You have the after cat oxygen sensors and we at Europe have the only oxygen sensors.

I remember reading somewhere that even the US/Canada model uses the after cat lambdas for fueling control and it only compares those values to front sensor to get idea of cat efficiency.