Hi fellow Jag lovers, HELP!!!
My '03 XK8 coupe with 90k miles has been throwing code P1647 (mostly) and P0153 (occasionally). Check engine light comes and goes, though mostly stays on nowadays. My independent Jag specialist changed O2 sensors TWICE, checked for leaks, etc., and is suggesting the ECU may need replacing and to take it to a dealer, as there is risk in other systems in the car "shutting down" if for some reason the ECU failed to talk to other components. This looks like a VERY expensive fix, with dealer likely wanting to replace O2 sensors (again) and a replacement ECU likely well over $1k. Spending $2k on a car that drives really well feels silly. I've seen ECU repair services online, though am worried about the car "shutting down" if ECU came back damaged somehow. Any recommendations?
Car drives great but exhibits some difficulty starting in slightly colder weather (anything less than 34f) and it's NOT a cranking issue, it turns over fine, just fails to catch, needing multiple tries at times, and other times firing right up. Was thinking maybe fuel rail pressure issue? I've also noticed recently, and only occasionally, a very slightly rough idle (as in not the usual silky smooth). Was also wondering if there might be some link between all of this?
No power loss, car pulls strongly, though fuel mileage a little worse than normal recently, off maybe 1 mpg.
Thanks!!!

 

Are you positive you have the right sensor? Upstream sensors need to be the wide band kind. The older narrow band sensors are used downstream. Folks have had good luck with the DENSO brand purpose-made for the car, nothing that needs splicing. Also, double check the sensor connector is put on the right harness connector behind the throttle body, I believe right and left are the same plug. These codes refer to bank 2, which is driver side in the US, so sort of under the coolant expansion tank. Of course, the heaters are on circuits with fuses. There are relays involved, too. I would double check it all before throwing money towards an ECM. These later ECMs are normally pretty robust, but there is a cooling fan that can be checked, and water sometimes fill up the bin it is located in when the bottom drain clogs.

Best of luck, keep us posted.

 

Doesn't sound to be the PCM (aka ECM). Maybe your current shop is out of its depth.