Unless you try to program something SDD will not cause damage. Just using it as a reader is reasonably safe. It does go through many tests before giving you the results - which is really good. I do not think it breaks anything if it craps out during the tests - so far mine has not done damage.
For proper results you are best to have the extra power supply attached - it draws quite a bit of power during the tests. If it drops too low in voltage you will get the virtual Christmas tree you see on your dash when the battery goes low.
I have used it in many less than desirable scenarios without problems - only bad info when voltage goes low. It does show you your voltage for computer and vehicle in the top right corner. If both stay green you are good to go. Orange or red will most likely show up phantom results. Orange vehicle voltage results can be useful if you are getting intermittent faults while driving, since you will see which modules fall out of com/function with low voltage.

 

Thanks, I don't even know how to use SDD properly. Did manage to connect it to the car but couldn't figure out how to pull DTCs. Couldn't find much info online either.

I don't suppose you can point me to a user guide/video or something?

 

If you want to go whole hog this gives everything! IDS-SDD-JLR Manual 02_02_12. Don't know if there is a newer one. You may be able to get it here: https://www.mediafire.com/download/x...l+02_02_12.pdf

 

Thanks again mate. Will give that a read!

Getting back to the matter at hand, do those upstream sensor results look right to you? They go down to minus 10mA at lowest, and only very briefly, but they NEVER go positive, not even once, not even at WOT or after lifting off the throttle or anything. That makes me think the sensors are failing. What's your thoughts? Can you check what yours do please?

 

Mine is up on the hoist at the moment to change out the rear track rod. Hope to get that done today. I will run Torque when I get it back outside if all goes well.

 

Thank you so much! That would be great 😃

 

Played a bit. I have a problem with my bank one. LTFT and STFT are maxed out adding fuel with a +1.43 ma on B1S1. Sharp throttle movement will drive the ma as much as 10 ma each way.
In Torque go into the Test Results screen and see what the problems are that it shows you. Mine shows slow response and out of range values for O2's.
Then go into Graphing screen and select B1S1 and B2S1 ma. It will show a much finer swing so you can see if the values are changing in an expected way. You can do it for any you want to see. However if you piggyback wide value readings the small swing will not show up well - you are better to see most readings, of the same type, on their own.

 

Thanks for that!

That's really strange, my B1S1 is always reading negative mA and the LTFT is up near 20%, yours is doing the opposite.

Do you have any screenshots you can share for comparison?

 

check out this post. I attached several plats whan I was playing with my 06 STR

https://www.jaguarforums.com/forum/g...-codes-239760/

 

Thanks, had a look there. My O2 sensors are definitely behaving differently than your good ones. I just dunno why they aren't throwing codes, any ideas?

 

I think you may be correct with the -ve ma driving high fuel trim. I put mine back on and as I was watching it the LTFT for my bank 1 dropped from the +20 down to virtually zero. The LTFTs and STFTs then were very low above/below or zero. Don't know why! Does not help you.
Instead of graphing or using the dial output in Torque just go to digital. Exact figures come up and are much easier to interpret.
I still think I have a lazy O2 sensor since the Test Results in Torque show too much time to go from rich to lean and too high a voltage output. I think I will put SDD on and get complete results. I was/ am not getting any EML type codes however SDD may show problems not shown by the basic OBD reader.

 

Thanks for the info.

Do you reckon I should replace the two upstream O2 sensors?

No matter what way I drive, they never give a positive reading. The more I read online, the more that doesn't seem right.

 

Watch the digital values in Torque. If they are moving in a reasonable range I do not think you need to change them out. The change is only small under normal operation. Only when you tromp it or let off quickly will it jump up to maybe 1o ma. With the increased SC pulley they will virtually never see a rich mixture so I would not worry about never going positive.
Remember the downstream are not supposed to act like upstream voltage O2s. The cats work on the flow to correct the excesses. Normally there is less swing than you might expect.

 

I've done that before, and the readings go from 0mA to around -10mA, but only briefly, they usually sit between -1mA and -3mA.

 

I'd say they are working perfectly! Waste of money to change them out. I do not think you have much of anything wrong with the O2 system or the mix control. What does the air/fuel ratio read? I bet it is very close to 14.7. The extra air from the SC is probably driving the requirement for high LTFTs. A remap should be able to compensate for that and bring them back down.

 

+20% Bank1, +18% Bank2.

Reduced performance mode all the time.

It's already been remapped and was working fine for months.

All work was done by previous owner which is a bit of a nightmare, but the car has had thousands and thousands spent on replacing everything it ever needed under his watch, with receipts for everything.

So demoralising. Thanks for all your help so far though mate its greatly appreciated!

 

Looks like you need to go to SDD. There has to be a number of fail codes there that you cannot see in Torque.
I must say I still do not understand how you can have boost at 9.6 PSI and still have vacuum at 10.4. Where does the boost go? The only supercharged vehicle I have played with is the VW Corrado. It always had boost feeding into the plenum. From minimal at idle to max when the dump valve kicked in.

 

I cant comment on the torque app other than to say if I thought it worked then I would use it.

and I dont use it. I use SDD. Its cumbersome but I trust the data. The live streaming is what you need to show. Like in my pics on my posts I linked above. A snapshot in time of just a current value is worthless. I want to see stuff scrolling by. Specifically I want to watch upstream and down stream over time so I can see if they are acting correctly with the right levels and switching (timing) and whether the numbers are drifting ir erratic

 

Thanks for all your help so far on this, guys.

Tomorrow I'm gonna hook up SDD and see if there's something I'm missing that Torque doesn't show.

One other thing: I noticed tonight that for the first 15 minutes of driving, the LTFTs were approx +12%, but the STFTs were approx -8%, then for the journey back home, the STFTs were sitting at nearly 0% and the LTFTs were higher too. The engine comes up to temperature after only a few mins, so I don't think its temp related, but does something change after about 15 mins driving? Does a valve open or something? Just a thought...

 

Here are my results. I reckon those O2 sensors are screwed. Genuine replacements ordered. Previous owner has fitted eBay ones that cost 23 quid :/