restricted performance xk8 2006
 

jaguar xk8 2006 convertible...comes up with P0171 code system too lean bank 1. Where is bank 1 and what needs to be done. I do not drive this car but once a week, but down the highway at 70 mph for about 10 mi. each way. Runs normally except if you step into passing, or floorboarding it. it will dye out but release foot and all is well again. Comes up with restricted performance but that goes out as soon as it returns to speed 3-4 seconds.

Do you have the OEM mass air sensor? The after market throw codes.

Sounds like a catalytic converter issue.

I'd at least take a careful look at fuel trims in case it's an air leak - costs hardly any $$$ for the OBD tool.

The "accordian" part of the intake tube often gets cracks in it after a while and leaks unmetered air. Mine did. Sometimes it's hard to see the cracks, but it's worth a gander.

^^ What he said. Loosen the clamps, remove the entire duct, and inspect the accordion section thoroughly on all sides. The engine bay heat tends to cause the accordion sections to split and crack as the years roll by....