Hi got a Toyota rav4 2002 2ltr petrol MIL lamp on checked the codes and have P0420 and P0430 both on any ideas what would give this?

Google says they are "Catalyst System Efficiency Below Threshold" one for Bank 1 and one for Bank 2
(don't know what a RAV4 counts as bank 1 & 2)

assuming you've no other issues like air leaks etc...
it could be a dead / dirty O2 sensor (aka lamda) bank 1 & 2 could be the sensor before and after the CAT.
or it could be a dead CAT but thats a bit less likely.

have you got a scan tool that will show you the live data from the OBD ?

[Edited on 1/2/2017 by mcerd1]

Sorry to jump in that looks interesting. How will "live data" be different. I mean what could it show and how would one use it differently?

Cheers!

Not able to see any live date just reading the codes with Bluetooth adaptor and the phone app. I find it odd that both bank 1 and 2 came on together.

live data would let you see what voltage the O2 sensors were reporting as well as checking other sensors like the MAF and coolant temps etc....

I agree you need to see live data.
If not there is a good chance you will replace part's that are not faulty.
Think of fault codes as a sign post to piont you in the general direction.
They are generated via the ecu as to what it can see as a result. Not always the cause.
Also the codes you are reading are not OEM codes just obd emission codes.
Get a reading from oem machine as these will be different. Probably !
You or they will also be able to read the live data and make a much better educated guess as to the problem.
How do I know.
15 years of working with reverse code writting for diagnostic machines.
Finally go to a diagnostic specialist most general garages do not have a clue how to interpret the information correctly.
Sorry to cause offence to any mechanics . I know I will get abuse.
Sent from my mobile
And yes I can't spell.

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Originally posted by hearbear
Not able to see any live date just reading the codes with Bluetooth adaptor and the phone app. I find it odd that both bank 1 and 2 came on together.

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Thanks for that will have a look it was torque I used to read the codes

thanks guys, question answered in spades
PS Sorry for hijacking a bit !

[Edited on 1-2-17 by v8kid]

Also check what voltage you had when the faults pinged. A low voltage could cause both Lambda sensors to be out of tolerance.

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Originally posted by owelly
Also check what voltage you had when the faults pinged. A low voltage could cause both Lambda sensors to be out of tolerance.

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Just clearing the codes almost certainly won't work P0420 and P0430 are there to flag up the cats are not working or not getting the right conditions to work --- ie it these codes are the engine's ECM predicting it will fail MOT emissions tail pipe test on CO or Hydrocarbons.

Diagnosing a P0420 on Paul (Scannerdanner) Danner's Youtube Channel https://www.youtube.com/watch?v=vyVnhCIMDnw&t=794s

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Originally posted by britishtrident
Just clearing the codes almost certainly won't work P0420 and P0430 are there to flag up the cats are not working or not getting the right conditions to work --- ie it these codes are the engine's ECM predicting it will fail MOT emissions tail pipe test on CO or Hydrocarbons.

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quote:

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Originally posted by hearbear
Car sailed through the MOT no problem thankfully, have been looking into this and had a U2U about a software issue Toyota had with this problem, don't think Toyota would be up for an update to fix it on a 15 year old car.

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