Fault codes - caused by throttle? (1.8)
 

I've recently had my throttle replaced, but now, after a couple 100 km, the check engine light has come on again.
TOAF reads the following codes:

- P1191
- P0445
- P0141
- P0420

Could it be the new throttle is causing these fault codes or do I need to look elsewhere?

Not sure how the throttle would cause these code - basically saying the O2 sensors are faulty in turn causing the Cat to throw an error code - also looks like you have a purge valve fault - saying that i had that on my ZT for 7 years without any obvious effect. :shrug:

Looking at the meaning of the codes as listed on this site most of the codes do look to relate to a possible problem with an O2 sensor or the associated circuit. Not sure if PO445 could also be related or maybe something else.

P1191 - Oxygen sensor heater circuit open circuit - downstream sensors Downstream oxygen sensor heater electrical - line break Yes

P0445 - Evaporative emission control system purge control valve shortcircuit Purge valve drive - short to ground Yes

P0141 - 02 Sensor heater circuit malfunction (bank 1 sensor 2) Downstreamoxygen sensor heater electrical - incorrect reading Yes

P0420 - Catalyst system efficiency below threshold (bank 1) Catalystgeneral failure - performance problem Yes

Had code P0141 on my car recently ,plus a couple of other spurious codes
Reset and deleted codes and ran until it errored again with P0141
Checked wiring to lambda sensor , which revelled nothing obvious so renewed rear lambda sensor and reset and erased codes , All being fine since

All of the oxygen sensor codes are probably related - to me this looks like the downstream sensor (post-cat) has failed.
This is the sensor you need: https://www.dmgrs.co.uk/products/rov...0722-mhk100728

P0445 is a little more unusual - I'd reset it once you've changed the oxygen sensor and see if it comes back.