Recently had 54,009 mile 2007 XKR supercharger pulled (by Jaguar Dealer Service - I know, $$$$, right?) to access the coolant hoses underneath that had split/failed.

Had them do the water pump, belts, hoses while everything was off whilst they farting around.

Got the car back and ran very well for a month ... I'm 66 and I run the living **** out if it, sport mode and floored at any opportunity.

Now I am getting occasional (and finding out predictable as well) "reduced performance" mode fault in the center of the dash cluster (where my TPMS is usually lit up due to beautiful after market wheels with troublesome TPMS SENSORS - uggh) and "check engine light" and I have narrowed it down to occurring after heavy acceleration, letting off the gas a bit, when I HEAVILY reapply the pedal is when I'm getting the fault.

Issue 'corrects itself' when I pull off road, shut off engine, wait a minute and restart. The check engine light is gone, "reduced performance" warning is gone and my trusty "TPMS" light is back on 😝

Reading all kinds of posts on this issue, running lean, running rich, O2 s sensor fault, CAT fault, supercharger coolant pump issue, auxiliary coolant pump issue ...

I don't know if the engine is saving codes from all this. I contacted my Jaguar dealer and waiting to hear back from him to make an appointment.

I'm running (since 47,000 miles/now have 54,009 miles) a VIEZU mild pulley upgrade and their 75hp/75tq tune which never gave me a problem prior to supercharger coolant hose failure.

Dealer knows I'm running this.

I really have resisted my impulse to go back to the original OEM tune and see if it still happens as I am trying to save the codes for the dealer to look at if in fact there are any.

Prior to the Supercharger issue I was getting CAT fault codes after heavy acceleration. The service rep and I actually talked about adding 'spacers' between the O2 sensor and inlet to avoid those.

So all that said, I'm interested to see what you might be able to share/add regarding my latest issue.

 

After 15 years, maybe the catalytic converters are starting to clog up a bit?
Also, you said nothing about any ECM codes. Those would be very handy to read. Also Live Data would probably help a good bit.

 

After 15 years, maybe the catalytic converters are starting to clog up a bit?
Also, you said nothing about any ECM codes. Those would be very handy to read. Also Live Data would probably help a good bit.




IDK ... I'd think CATS function would decrease by usage (miles driven) rather than age but I'm no expert by any means - don't have a code reader, the codes are clearing out when car is turned off and turned back on, the CAT codes I threw prior to Supercharger issue had to be cleared before the check engine light would turn itself off, not the case here, IDK if they are stored and can be found by the dealer service tech.

I read in some threads about the same issue that it's difficult to find the codes that contribute to it.

That's one of the issues I'm wrestling with is I could go put the OEM tune back in and see what happens, reinstall my aftermarket Vizeu tune and see if the problem persists.

The service manager told me about the spacers for the O2 sensors that space them back from the exhaust pipe far enough that they don't catch the changes emissions to throw any codes (ie: CAT codes)

thanks for your thoughts, hoping that someone has experienced this exact issue and we have some and input.

 

My thought is that service folks hit the gas hard several times and the cats finally had enough. If spacing the O2 will prevent the fault you know where your next investment should be.
wj

 

Ceejay was asking about DTCs, diagnostic trouble codes which may pinpoint the exact problem rather than guess... You should be able to go to any chain auto parts store and have them run a scan, even if restarting "clears" your error, there should still be stored codes.

Also how long have you been running the Viezu tune?

 

One of the cats on my '07 XKR failed at 29,000 miles.

You definitely need to get the car scanned for codes though so you don't go wasting time and money on the wrong things.

 

my bet is on clogged cats too. Bungs on the O2 sensors will provide no value in this case.