Question

2001 Jaguar S Type V8 with engine code P0174 only idle rough and a loud nock. Where to begin?

Answer 1

P0174 Fuel trim lean Bank 2

Loud knock , the knocking noise has to be found out, A mechanical problem  can and does causes the CK ENG LT to set, But only a visual inspection will lead to find what is causing the loud knock noise.

Answer 2

P0174 JAGUAR - System Too Lean Bank 2
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