My jaguar 2001 s-type 3.0; just failed inspection for emissions. The code was p0420 code. Bank 1 catalyst below threshhold. Rather than get ripped at the jaguar service center. I will buy the part myself and fix as I have always done. Where is the bank 1 catalyst located. And should I also replace both oxygen sensors? Someone told me that replacing the oxygen sensors may fix the problem. What should I do? Thanks

SOURCE: knock sensor location

It's under the intake manifold. To access it you have to remove the manifold and injection rail.

Colin Stickland

• 22516 Answers
• Posted on Jan 10, 2009

SOURCE: cataliyst converter bank one; heater valve; etc. for Jaguar typeS

change O2 sensor their cheap enough ,heater valve not sure about ,seat and mirrors is either a fuse or a relay

SOURCE: I have a P0420 code catalyst efficiency below

it is a bad converter not o 2 sensor i would change the cat and both o 2 sensors

SOURCE: How do you find and replace a 1rst bank knock sensor on a xk8

13mm socket in between intake tubes on right side of motor(pass side) very easy.

SOURCE: engine light on 3 codes in system

The lean running codes are related to the p-1000 code...

Running lean on bank 1 and bank 2 means your oxygen sensors sense too much oxygen in your exhaust flow. This means either your engine is getting unmetered air (air that the engine does not know is coming in, therefore does not send fuel to compensate for...) (air that your mass air flow sensor does not see). You could have either a bad mass air flow (MAF) sensor (in the intake piping after the filter; this sensor tells your engine how much air it's taking in, so it can send the right amount of fuel through the injectors to properly burn with the air available with as little emissions as possible), or you could also have a cracked/broken intake piping after this sensor which lets air in the intake that the sensor does not measure... A large vacuum leak could also let unmetered air in the engine.

Or... Another possibility here would be low fuel pressure (bad fuel pump, bad fuel pressure regulator, fuel leak), as not enough fuel for the air would also cause the same lean condition.

It could be that some oxygen sensors are bad...

These conditions are hard to pinpoint exactly unless you have a scanner that can read sensor data (MAF Flow, fuel pressure, oxygen sensor values)...

The first thing I'd do would be to check for cracks or damage in the intake piping... If there is none, then it might be a low fuel pressure issue, or sensor problems...