Why does my car run lean on bank 2 - 2005 Jaguar S-Type

Probably is the Oxygen sensors are bad seems i had same problem a few years back and had to replace the sensor. Hope this helps

Code 171 and 174 are for bank 1 and 2 running too lean. The engine has compensated as rich as it can go, and it is still to lean. This does not necessarily mean your mixture is bad, but something (a sensor) is telling the ECM to correct lean. The oxygen sensors alert the ECM to how lean/rich the exhaust is, and then the ECM trips a code. Maybe you have a bad oxy. sensor, but since there are 4 of them (2 per bank), I don't think they could all go at once.

code P1128 02 sensor bank 1 lean
code P1129 02 sensor bank 1 lean to limit
code P1133 02 sensor bank 2 lean
code P1134 02 sensor bank 2 lean to limit

fuel system is lean.

If both banks are lean you may have a vacuum leak or an EGR problem. My want to do some checking before you replace parts. Would be unusual to have 2 bad o2 sensors at the same time. Lean conditions are caused by too much air and not enough feul. A restricted feul filter can sometimes cause the same problem.

Because you have a V engine the pistons are angled, More commonly known as a Bank, Now Bank 2 lean would mean that the righthand side as you look at the engine will be Bank 2, Lean means that bank is running rich, using more fuel

If bank one and two are running lean problem is the Mass Air Flow Sensor (MAF) Dirty or Defective.

you may try your rotor button and distributor cap. and spark plug wires. try your map sensor also they tend to cause a lot of misfiring if they go bad.hope this helps.

why is my navigator running lean thats why my check engine light is on

Bank 2 is generally the passanger side. Recently, We have run across a few system to lean codes in Fords. We have ended up changing the O2 sensors.

Most likely cause is the intake manifold gasket