Hi eveyone,

I was driving the car with my nefew who visited specially to see it, and while accelerating on the highway ,all of a sudden, the car started to slow down, warnings showed on the dash screen and the engine yellow light poped, a few messages appeared too amongst which i think I read something about Cat and "stop the engine" or something.
I parked, made a ODB2 reading and the code P2105 appeared (along with the P0401 even though the EGR Valve is BRAND NEW out of the workshop) and P061A too.
I stopped the car. Waited 2mn and started again and the message dissapeared and managed to get back home 10km from there...

that's extremely stressing and scary...
I found this https://www.carobdcode.com/p2105-jag...oogle_vignette

But could a user explain me what it exactly is and what should I do?
I don't dare to use it anymore although she's just ouf from the mechanics for the EGR and fluid renewal (Engine oil, assisted wheel oil,rear axle oil, all filters new, supercharger oil,air filters,new EGR valve ..).

Any help would be welcome.
Thanks.

 

Remove nefew to clear problem.

Since you had the EGR replaced which requires the the throttle body to be removed I think there is some relationship here.

 

I'm not saying definitively, but "It's the Battery". I always say that because 75% of the time It's the Battery.
Drive-by-wire is affected by low voltage, and since a critical system, any fluctuation will cause a fault.
Check the battery, 12.6 volts after sitting for many hours. If not, have it load tested AFTER it's charged fully. NOT with a maintainer nor a trickle charger.
After the battery situation is rectified, reset the code and try again. If it reappears, THEN start more in-depth troubleshooting. Scary, yes, but don't panic YET.

 

Hi @Cee Jay and @McJag222 .
Happy new year to you both. whishing you a great health and lots of shared joy.
Thanks a lot for your answers that helped calm me down...Right after the trouble I called my friends claiming I'll sell that car as I never planned to get another source of stress...
Anyway, Yesterday I checked the battery and it told it was half charged. So I disconnect it and fully charged it which took 2hours to reach the peak .
I then reconnect and started the car, let it turn for around 25mn playing with the pedal occasionally and it showed nothing on the DTC read.
Haven't drive with it though as the weather was more than ugly and having the car out from the house parking is not an easy task...
I'm surprised the battery was only half charged as the car was fully charged a week ago but just read about others battery problems and understood they are even worst with low temp...
Will install a Ctek plug in the trunk and get a 10A Ctek charger so I'll keep it plugged like an Electric Car when in the countryside...The problem will be how will I do when in Paris as there's no plug in the underground parking and I leave it parked for 3-4 days usually...

While the EGR was replaced I had the throttle checked as the mechanics had to take it off, and it was looking clean ,the coating having turned yellow like an old varnish though, and the rubber junction between the plenum and the throttle body was replaced by a section of silicone tubbing . I hope they didn't break anything. Until that trouble I felt the car was breathing much better and the car noise when accelerating was even sweater.
I really hope the problem was just battery related..

thanks again for your help.

 

that’s the torque monitor. it’s intentionally aggressive and monitors app demand to throttle position and engine speed among other things. last one is critical. plenty of cases of people doing heads and bending the crank sensor window instead of holding the balancer, put it back together and you get a p061a

it’s better to have you on the limp home spring than a self accelerating car.

 

Hello @xalty , Thanks for your answer.
I'm about to change the battery for a new one as the previous one apparently doesn't hold anything .
Fully charged on friday, it shows 12,6V on saturday and I replugged it today (monday). It was down to 12,16V... Tonight it was so low the car trunk didn't even open.. (it's 26F these days).
So I just ordered a new bigger battery 110ah /920A .The actual one is 90ah/850A.
I really hope it'll solve the problem... haven't dare to drive it since last saturday and that trouble...

So, I understand half of your message (sorry I'm not expert yet with car electronic), could you please give me details about what should I check, what should be done, and what are the dangers, if all that is not related to a dying battery.
Thanks.

 

An ‘08 xkr. How many miles on her? Are those the original cats?
Cats are filters. Filters get soiled over time. If there’s excessive restricted flow in the exhaust…
Though not directly related to the throttle actuator, i wonder about the actual root cause for the ecm response.