VXR8 fault codes

[maxmc2]

Afternoon all.

Had these two fault codes pop up yesterday, just wanted to make sure there was nothing untoward here, personally I think not.

P0420 - Catalyst system efficiency below threshold bank 1
P0430 - Catalyst system efficiency below threshold bank 2

Thanks as always.

[vxr2010]

Are codes on all the time ? Have you deleted them and they have come back , I looked on line and it showed a number of causes strangely the cat going bad is the least likely ?

[maxmc2]

vxr2010 said:

Are codes on all the time ? Have you deleted them and they have come back , I looked on line and it showed a number of causes strangely the cat going bad is the least likely ?

Only happened yesterday and have now deleted them, currently have a full pacemaker system so wonder if it's just something to do with aftermarket cats.

[ringram]

Very likely.
Just disable post cat sensors. Job done.

[rich24v]

Post cat sensors, normal event with aftermarket cats.
Simple entry in the tune to delete affect of feedback.
There are physical o2 sensor extender things you can
buy which are supposed to fool the ecm......

[Tattooboy]

Had to fit spacers on mine when I changed the headers and cats, they worked fine.

[neiljohnson]

As Said it's the cats not as efficient as the stock items but the exhaust has been on a while now so if it only pops
up every few months it's not really an issue
You can fit the spacers & they seem to do the job on the vxr8's I've fitted them too

Failing that an adjustment in the ecu will turn it off permantly
Obviously if your going into the ecu to do that then a good excuse to remap at the same time

[maxmc2]

neiljohnson said:

As Said it's the cats not as efficient as the stock items but the exhaust has been on a while now so if it only pops
up every few months it's not really an issue
You can fit the spacers & they seem to do the job on the vxr8's I've fitted them too

Failing that an adjustment in the ecu will turn it off permantly
Obviously if your going into the ecu to do that then a good excuse to remap at the same time

I'll have a chat with you about it when I bring it down for its MOT.

[vaxer]

did this ever cause fuse 32 to blow at all?

[maxmc2]

vaxer said:

did this ever cause fuse 32 to blow at all?

Not that I am aware of, what does fuse 32 run?

[vaxer]

Having read your post again, we have slightly different error codes, but I'll reply anyway

Fuse 32 is in the fuse box under the bonnet - it's labelled as 'Emissions' or something similar in the manual - mine recently blew and threw up 9 (yes) error codes, and also stopped both radiator fans from working. I've now got my local mechanics trying to solve the problem (couldn't get the car as far as Walkies). The fuse also covers various emission sensors.

We're trying to work out what has caused the fuse to blow - something between a dodgy fan motor (although I've managed to get both fans running by replacing the fuse, getting the car up to temperature and them firing up the aircon) so it may not be that; a dodgy O2 or other sensor; or, God help me, some fried wiring somewhere....

The codes read when the fuse blew were:
P0036 HO2S Heater control
P0056 HO2S Heater control
P0480 Fan 1 control circuit
P0481 Fan 2 control circuit
P0054 HO2S Heater resistance
P0056 HO2S Heater control circuit
P0060 HO2S Heater resistance
P0141 O2 Sensor heater circuit
P0161 O2 Sensor heater circuit


The reason I was asking originally is that someone on the G8 forum had a problem similar to the above which then led to the P0420/P0430 problem you mentioned....

[vaxer]

Quick update - after a thorough investigation today of the wiring loom and all the connections unplugged cleaned and reconnecetd, the fault seems to have gone away ...for now at least. Fair play to the lads at Super Duper Garage in Basingstoke for sticking with it.

[vaxer]

p.s. Sorry to hijack the thread