P0422 Main Catalyst Efficiency Below Threshold (Bank 1)

[winty234]

Any idea's where to start with fixing this? cheapest way possible? will appreciate your comments guy's. Cheers

[david.aka.judas]

can you replace it with a sports cat??

[winty234]

how much you looking at though?

[david.aka.judas]

a universal 200 cell cat is about £100 from ebay.

but check from others or your vx garage if its needed first.

[winty234]

anyone got any idea's on just sorting the fault? which sensor or could it be any?

[LADmachining]

First thing to check would be the operation of the two O2 sensors on bank 1.

If these are OK (both reading the same, values changing in sync with each other), then the cat is knackered and should be replaced.

Normally, the sensor after the cat will show very little variation in value. It's output will increase if the efficiency of the cat decreases.

[winty234]

First thing to check would be the operation of the two O2 sensors on bank 1.

If these are OK (both reading the same, values changing in sync with each other), then the cat is knackered and should be replaced.

Normally, the sensor after the cat will show very little variation in value. It's output will increase if the efficiency of the cat decreases.

Cheers matey, what's best way to test if its the O2 Sensors?

[david.aka.judas]

http://www.lambdapower.co.uk/diagnos...stic_index.asp

[chaz851]

sorry to resurrect an old topic, my 3.2 v6 has had this P0422 alarm for a couple of months, Ive cleared error and just done again.
its running fine, we have just done best part of 1000 miles to France and back over the last week, light on and no problems.
its a 53 plate with 144500 miles on. more into bikes , would this be the cat?
being V6 with two tail pipes would there be two cats? if so which one?
I can work my way round bike repairs 1930's to 2010's but cars I just drive them.
thanks