Hey everyone I have a 2013 jaguar xf 3.0 v6 supercharged I recently replaced the engine with a 55k Mile motor it runs well but once I do a full throttle pull it doesn’t feel as all the power is there check engine doesn’t flash and during normal acceleration it drives amazing. at first the car threw a bank 1 knock sensor low voltage so I went ahead and just replace both with Autozone knock sensors, torqued to the spec all data provided and now I have a code for both sensors saying they have low voltage. Main battery was replaced my secondary battery is bad but from what I know it just controls the start/stop function. Thank you in advance!

 

Can you check for codes? Sometimes a lack of power can be the IC pump not running. But again that will set a code to guide you in fixing it.
Auto zone does not sell Jaguar parts. What part number and brand did you install? That is a GIANT red flag.
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