depends whether you want a GM one or not........how long do you intend to keep the car???
look at this tread it might help......
http://www.omegaowners.com/forum/YaBB.pl?num=1202932346
Trust me make sure your sat down when you get your quotes
and i would speak to ANDY C he sorted mine out for me and way cheeper then getting it myself from VX.
Nothing wrong with your CAT's (and if there was you'd be looking at £711 each side).
You have Codes P0420 and P0430, reset the codes and run some cataclean through the system. The codes still come back but just a case of reseting them when they hit the threshold.
Ifyou do an emissions test i'm sure you'll find they are still working fine.
Basically it's the precats which are the trouble (only seems to happen on the 3.2, though the 2.6 shares the same setup).
Basically the precats aren't good enough for the job although the main cats are, hence why if you do an emissions test you will find the car would pass no problems.
There are a number of us 3.2 owners who have this re-occuring issue, Kevin Wood, SP3.2 and I for a start.
The EML comes on when the lambda readings have added up to a certain level (hence 'threshold') over time. Better quality fuel and Cataclean seems to help but the problem remains that the precats aren't big enough to do the job.
QuoteBasically it's the precats which are the trouble (only seems to happen on the 3.2, though the 2.6 shares the same setup).
Basically the precats aren't good enough for the job although the main cats are, hence why if you do an emissions test you will find the car would pass no problems.
There are a number of us 3.2 owners who have this re-occuring issue, Kevin Wood, SP3.2 and I for a start.
The EML comes on when the lambda readings have added up to a certain level (hence 'threshold') over time. Better quality fuel and Cataclean seems to help but the problem remains that the precats aren't big enough to do the job.
Thanks for the info. :y So hopefully I might not have to replace the cats then. Is there any complete solution to the problem or is this something us 3.2 owners have to live with?
Mine has done this a couple of times too. >:(
It seems to be that either the pre-cats are not quite up to the job (by design) or the ECU is expecting them to be working in situations when they aren't.
Either way, the main cats work fine. My emissions barely showed anything on the HC and CO measurements to MOT in December yet the damn light came on in January.
I would just get a cheapo code reader to reset it when it happens and ignore it.
Certainly don't worry about shelling out for cats unless they are proven to be knackered by an MOT emissions test.
Kevin
Bob .. some discussion going on here :
http://www.omegaowners.com/forum/YaBB.pl?num=1202857680
I've just bought one as well shade over £30 with postage .....
ebay item no 310021810151
:)
Bobs local parts manager has just cancelled the order for a large tub of vasaline ;D
May sound stupid but what are 'Cats.'
(I'm not the best at Mechanics) :-[
Have any 3.2 owners suffering this changed the pre cat (or post cat for that matter) lamdas?
QuoteHave any 3.2 owners suffering this changed the pre cat (or post cat for that matter) lamdas?
I'm sure someone did a while back.
However, Marks_DTM did some digging and reckoned it's a known problem that the pre-cat can't cope well with the exhaust flow rate of the 3.2 engine, so changing Lambda sensors is unlikely to cure it. :-/
Now I've got an ELM cable I want to find / write an application that will log live data so I can get a baseline for what these sensors should be doing, and see if anything changes when the problem occurs.
Do you know if there are any updates available for the engine ECU for the 3.2? Just wondering if they've issued a firmware update with wider limits on cat efficiency?
Then again, VX are probably making a fortune on all the cats and Tech 2 sessions. ::)
Kevin
Now I've got an ELM cable I want to find / write an application that will log live data so I can get a baseline for what these sensors should be doing, and see if anything changes when the problem occurs.
I have seen the codes individually, though possible different sequence of events.
The implecation of the code is that the pre (main) cats lamdas are getting a signal, but the post cat ones are getting a signal that is not plausible? So if it was pre cats, should that effect pre (main) cat sensors, main cat, and post cat sensors?
Doesn't scantool.net do live data?[/quote]QuoteNow I've got an ELM cable I want to find / write an application that will log live data so I can get a baseline for what these sensors should be doing, and see if anything changes when the problem occurs.
Yes planning to do the same with my scanner, perhaps we should do some comparisons Kevin?
Ahhhh! Me understandy now :yQuoteI have seen the codes individually, though possible different sequence of events.
The implecation of the code is that the pre (main) cats lamdas are getting a signal, but the post cat ones are getting a signal that is not plausible? So if it was pre cats, should that effect pre (main) cat sensors, main cat, and post cat sensors?
As I understand it (and it's a rather limited knowledge), the ineffecient Pre Cat is not doing it's supposed job, so the first sensor will read higher readings than the 2nd sensor. presumably this is going to be worst at cold start times when the enrichment programme is running... ie. pre closed loop operation.
May sound stupid but what are 'Cats.'
(I'm not the best at Mechanics) :-[
When mine has lit the emissions light it has been shortly after the engine has warmed up, although once that coincided with filling from empty from a petrol station I don't usually use.
I wonder if the 1st stage cats fail to work after the specified time sometimes, or allow some dirty gases through during high load, and such events are counted up and cause the light to come on if it happens too frequently?
The post cat sensors are behind the 1st catalytic convertor (of 2) in the system (in the exhaust elbow just under the manifold)but before the main cats. These sensors will behave the same way as the pre-cat sensors until the 1st stage cat starts cleaning the exhaust gases, when they will just read rich (since the sensors work by measuring excess oxygen in the exhaust and the cat uses up the oxygen breaking down nasties).Is that right? I though pre cat sensors were after precat but before main cat (so on elbow), and post cat ones are post main cat?
Is that right?
If it's shortly after the engine has warmed up then I guess we can assume that the Cat heaters have either gone off or are intermittent at this point.... So logging doesn't start until operating temp is achieved at a guess?
The way I understand it is that the pre-cat sensors control the mixture. If the mixture went out of the closed loop range or anything was suspicious about their operation they should raise a different code.
The post cat sensors are behind the 1st catalytic convertor (of 2) in the system (in the exhaust elbow just under the manifold)but before the main cats. These sensors will behave the same way as the pre-cat sensors until the 1st stage cat starts cleaning the exhaust gases, when they will just read rich (since the sensors work by measuring excess oxygen in the exhaust and the cat uses up the oxygen breaking down nasties).
I suspect the ECU is looking for the 1st stage cats to start working after a warmup period (maybe using a richer mixture, retarding ignition, delaying gear changes, etc. until they have woken up).
When mine has lit the emissions light it has been shortly after the engine has warmed up, although once that coincided with filling from empty from a petrol station I don't usually use.
I wonder if the 1st stage cats fail to work after the specified time sometimes, or allow some dirty gases through during high load, and such events are counted up and cause the light to come on if it happens too frequently?
I have seen the two codes in my ECU without the light having come on too, so it could be that the problem gets logged at one level and lights the light if it persists.
In any case, once the main second stage cats start working the exhaust emissions are fine but there is no monitoring of the second stage cat efficiency.
Kevin
This is also when my EML came on and shortly after filling up at Sainsbury's.