Howdy folks! I'd like to know how to get my 2006 XKR performance back.
The dealer informed me while doing routine service (oil change under warranty) that he was going to implement some required programming change to reduce emisions as required by some change notice. He said I wouldn't like. At the time I didn't thing much about it. The car used to do 145 MPH, now only 130 MPH. I can definetly tell the difference off the line. Anybody else have this experience, or comments?

 

Without knowing exactly what the dealer did it is hard to know/say, but I am surprised your XKR goes so slow to start off with?

I easily get over 150 mph and in my friends 4.2 (we have derestricted it) we get more like 170mph.

I personally have driven a 2005 XKR @ 179mph and that was un-modified

 

Thanks for the feedback.
I will do some more investigation on this.
I really like the car.
The dealer wants me to buy a new one, but why should I?
This one with 32,000 miles doesn't perform as advertised.
When I told the service manager I had it up to 145 MPH he acted like it wasn't supposed to go that fast!
Maybe I can figure out how to get the dog to run as good as your experience dictates.

 

These XKs are restricted to 155mph, I think you need to emphasize to the dealer the key word being restricted.

It sounds to me he wants to sell you a new XK rather than fix your old one

 

Or maybe you can decide you don't really need to be going 155+mph


Doug

 

Huh? The dealer (near Pearland, TX?) reprogrammed your car to meet some new??? emission standards???? that were "required"?

Required by whom? What standards? I've never heard of such nonsense!
Now your car only goes 135 mph? That's unacceptable and you should demand it be changed back to stock. Whoever heard of emission standards being made retroactive???

Humm..Brutal works for a dealership near Pearland, TX. I'd ax him what the hell is going on. What good is an XKR that can’t overtake a school bus?

 

It was the dealer on the SW FRWY.
Here are the details of the service report:

F J004 ODB11 DEF
CAUSE: REPROGRAM ECM & TCM
869960 REFLASH ECM AND TCM -X350
1303 WCJ 0.40
1 JLM21848X LABEL
FC: 82 PART#: COUNT:
CLAIM TYPE: 04
AUTH CODE:
J004D
23470 REFLASH ECM AND TCM

The car is now out of warranty and I'd like to get it to run as advertised when I first bought it.

 

I hope you are not doing those speeds on roads with others doing THE SPEED LIMIT.

 

I had gotten this same J004 notice from Jaguar and basically ignored it. At least until I got my yearly renewal from Kalifornia DMV and the renewal form specifically required that I show proof of having done the J004 work. From other discussions I have seen about this "emissions recall" my understanding that the reprogramming did NOT have an effect on performance and was actually pretty harmless. Maybe the dealer you went to is pulling your chain.


Doug

 

Only after I have had a few beers


Seriously thou......We did it around the Milbrook Bowl

 

XKRACER, would love to know how to derestrict the governor!

 

A Ford dealer did this reflash to my 2004 F250 PowerStroke in 2005. They say they can not go back to the old program because their programmer only holds one program at a time.

I now have a 2004 F250 PowerStroke Diesel that runs like a Ranger. I lost power, the shift points in tow haul mode were changed so it never drops into 1st gear unless you stop. I was more than PO'd but nothing that I could do about it then other than buy an aftermarket programmer for $500 and a set of performance programs.

 

Trust me I have been asked that a few times!!!

I was not allowed to see how they did it but I can tell you the traction control was offline, the speedo did not work, we had a GPS reader on the dash top showing our true speed, also the ABS was not working.

What I can tell you also is, to do this he pulled one or more fuses from the lefthand side engine bay fuse box. I did ask him but he said Jaguar swore him to secrecy.

On my mates 4.2 he had the ECU remapped at Viezu which took off the restriction as well

 

I had the J004 flash done a while back and yes performance was effected briefly but it was mainly due to the tranmission programming being reflashed as well. You will need to have your transmission logic re-adapt to your driving style. There is a proceedure for this somewhere in the FAQs.

Your top speed performance may be affected by the new ECU program's effect on throttle settings. As mentioned many times in this forum sometimes the pedal on the floor does not produce WOT so it should be checked while it is on a OBD scanner.

 

Which again brings up the issue as to why there are no simple devices available for us or affordable piggyback boards in order to tweak some changes? The first thing I did when I had my Corvette was to buy a Hypertech programmer, and there were a bunch of products available that allowed for similar tweaks, the most notable of which was the LT-Edit software for laptops. All of the products were typically in the $300 to $500 range.

It seems like these types of products are available for many other cars out there so why is there nothing for the Jaguars? Is it something about the complexity of the ECU on our cars or does it really come down to lack of a market for someone to go through the trouble of developing software for a laptop that would allow tweaking?


Doug

 

I had D-P Tuner in Houschton, GA flash a 80 hp econo tune on my 03 F250 for $75, and I cannot keep my truck on the ground. Increase of 2 mpg too. They're easily found on the internet--see Dieselstop.com forum performance blogs. Just about any vehicle nowadays has a ECM tune change available.

 

Bamama, no most vehicles do not have performance tunes, limited markets and limits parts. See jaguar small market. Check euro toys and others that deal with jaguar performance. Forget others theyre not gonna develope something for such a small market.

OP Youre the first that has ever mentioned anything about the j004 performnce, yes the trans reflash clears "your" learned adaptations, but they will relearn your driving style again eventually. It cannot be returned back to "before" against the law since its a federally mandated recall. But Ive never seen a heard about a performance drop from anyone else. I would call eurotoys and get them to do a reflash, youll be power ahead over anything in a stocker. And as for top speed....if you pull the fuses for the abs module(sends vehicle speed across network) the car doesnt know how fast its going and you have no speedo, trac etc like racer said. On my nissan i simply installed a switched fuse to turn on and off from the dash to disable traction control and therefore can smoke the big offroad tires at will leaving people wondering how the hell a big lifted 4x4 with a 6 cylinder can do that and its disables top speed limiter also although ive already done that with uprev nissan software and programming