I understand how frustrating it can be. One problem is that it may only people with the 2013 and 2014 V8S who will potentially share this issue with you. Anybody with a newer model will have one that has already got the newer O2 sensor setup and many who have the older cars or have recently bought older cars will already have had be recall and simply didn't notice. It was confirmed by to me by the tech that the standard (pre recall) '14 V8S is louder than the standard '15 R. I'm surprised your car has lost ALL the pops and cracks though. Ironically, I find that very disturbing for all the wrong reasons!

 

My instinct is that it isn't just the O2 sensor that would kill your pops and cracks. I can hear my valve pump whirring away at low speeds all the time and as far as I'm concerned, it's supposed to do so. I wouldn't consider risking having that messed with for fear of losing some of that characterful sound. It feels to me more like something in that mechanism isn't doing what it's supposed to do now that it's been reactivated.

 

Well, this seems easy enough to demonstrate conclusively with a couple cell phones.. decibel meter and video recording...

 

That would be an interesting test. If you can get both models in one place and replicate the same throttle inputs and ambient noise for both 😉

 

I think we can get close enough that if there's an appreciable difference it'll be noticeable. I'll volunteer my '16 R. Want to figure out similar conditions and use your '14 V8S?

 

let me know what decibel metering app you want to use and I'll have a go and post my results

 

Also, let's agree on settings (active exhaust on/off), temperature, number of rpm.

I'm assuming we will rev gradually and not to create pops?

 

I don't suppose you know if we're talking about the K309 service action here? This applies to both 3.0 and 5.0 as well as all VINs from K00001 to K29970.

My V6S has had it and didn't change the car (or exhaust) one bit.

Text from the service action says:

To address concerns with the correct operation of the Oxygen (O2) Sensors, new engine module software is required on the models, engine variants and Vehicle Identification Number (VIN) ranges described above.

At the next service opportunity you are requested to reconfigure the Powertrain Control Module (PCM) with latest level of software.

In the nicest possible way, if OP is concerned that people are finding it hard to truly believe what he's saying, post a vid as mentioned several times before and we can stop guessing/assuming!!

 

Yep, agreed. We need to iron out all of those things and others such as exact placement of the sensor. I think it'd be best if an expert determines the exact test procedure rather than myself in order to ensure we test in an optimal fashion. Perhaps someone like unhinged or VMaxTuning?

 

Interesting. I'm not sure about the specific action codes nor whether those actions would have a different effect on V6 and V8 models

 

Well, at least one V8 has had it too (plenty more I'm sure) and no reports there either.

https://www.jaguarforums.com/forum/f...-stock-153184/

 

I for one run with active exhaust on at all times. I reckon I'd notice if there was a change to the soundtrack. I suppose it'll be hard to avoid this service action when my next scheduled service comes along. I'll be sure to pick brains and pay close attention when that day eventually comes. I wonder if my warranty would be effected if I refused to have that done.

 

As with my '76 Land Cruiser and '90 GMC Sierra Sportside, I have.

 

I have no sound measurement experience and would defer to others on this matter.

 

I stand corrected

 

I had the K309 update performed on my car prior to the tune and noticed no change in sound level. Perhaps, the sound reduction is market specific and hasn't been done here in the US.

 

Well there's a few things going on here, let's try to address them one by one before this turns into a big confusing mess...

1. I asked my "inside contact" at JLR about the O2 sensor recall/update K309.

The updated software only changed the Air-Fuel adjustments for hot and cold starts, there was no changes to the fueling or ignition at wide-open-throttle. Also no changes to the function of the exhaust flaps. No changes to the "controlled misfire" which makes the pops either.

And in fact this update was only applicable to vehicles with Euro 5 and Federal (US) emissions, there were no changes made to Euro 2 or Brazilian E22 vehicles.

The "O2 sensor calibration" aspect was in relation to the "set values" for hot & cold starts, which is also part of the changes made to the AFR target values during starting.

So your dealer is making up stories.

2. If your car has lost it's pop, it's very likely to have lost power as well, which should be noticeable from behind the wheel.

That's from him.

From my point of view, you should get the car onto a rolling road, get a power measurement, and also check the air-fuel ratio's at the tailpipe, not just at full power but also at cruise. There might be something else going on here that has been missed.

For example, choked cats could stop the pops, and there's "no code" that will tell you cats are choked up.

Also, it's not impossible to reflash the older software back into the ECU, even if the dealer says he can't, maybe he just doesn't know how (it's not a standard procedure) but for sure it can be done and since you are in the UK a JLR Field Service Technician isn't far away. And he should be able to do that.

If you are 100% convinced that the loss of noise came from the software update, then putting an old version back in should bring it back. So insist on that.

 

This "software update", if i have a remap already on my car, will the update wipe it off??

 

Yes it will.

 

+1. A good tuner will keep a copy of your tune in his/her library and should be willing to re-flash for free if you lose your tune for whatever reason.