2004 156 JTS CATALYTIC CONVERTOR

[ForzaSab]

For quite some time now i've had this sound on startup that of a blowing air type of sound.
I thought it was a cracked pipe or something so i took my car to a well known exhaust place in Geebung (Brisbane) and even they didnt know what it was and they are supposed to be the experts! lol
Recently i had the head gasket done at Alfamotive here in Brisbane and they told me it was most likely a crack on the welds for the extractors, or something like that, and that it was common due to the type of welding that was done at the time it was made.
Today i am driving along and i suddenly felt a drop in power, straight away i thought COIL PACK!! but there was no flashing lights to alert it was in fact that. I then put the window down and could here it was something to do with the exhaust so this arvo i went to an exhaust place in Tingalpa and pretty much straight away they told me its most probably the catalytic convertor is falling apart, without a more indepth look they couldnt tell me anymore.
My question/s is...
1) I dont want to pay the ludicrous amounts of money ($3000-$4000 i have seen some people say a replacement is so are there other aftermarket options?
2) Do i need a catalytic convertor? I've read some people have put in a resonator in its place or a "dcat"(whatever that may be).

My wife is understandably getting to the end of her tether with this car so i need to explore my options.

[L4OMEO]

Gidday,

There are a few (ok, probably all of them) members on the forum better qualified than I am to venture a technical opinion, but if you don't get the advice you need here then my recommendation is bring your car to someone who knows that model and has encountered their particular problems before. It will save you time and money, experience counts. Cough up for an accurate diagnosis and from there  you can research your options for getting it repaired (seek further advice from the forum, shop around for a quote if you're not happy with the first, source parts from overseas - great exchange rate at the moment). I'd suggest calling Cameron at Automotion in Albion and see what he says, he's looked after me well.

Nothing will help you locate the end of your wife's tether quicker than having problems with your car 

Best of luck
Rory

[wankski]

are you talking about the primaries or the main cat?

I would not advise de-catting... the system requires a voltage difference (diff readings) b/w the twin lambdas in the primaries (precats) cf the final lambda after the main cat. I am 90% sure removing the main cat will result in a engine light.

If primaries I would start looking at aftermarket headers that delete the cat. In theory, i'm sure a new efficient main cat will result in correct readings and all will be well, plus u pick up a few ponies due to the lack of twin cats in the manifold...

Supersprint makes such a set of primaries.  (far cheaper from OS)

and yes, the stock manifolds are BS expensive...

[wankski]

btw, is your car in excess of 100k kms?

[ForzaSab]

cheers for that wankski...
my car is at 72000kms approx atm.
Until its pulled apart im not sure where the problem is.
So if im reading this right your saying i can pretty much get the 3 cats ripped out and have an aftermarket one installed at a much cheaper price and get more bhp, is that right?

[wankski]

geez, 72k and u've done a HG and had the manifold cats fail??

to be clear i'm saying if the primary lambdas continue to read ~2.2-2.4v (near stoich) and the final lambda read normal, the ecu won't know the difference.

Its possible since the pre cats lambdas are just that - before the cat, so the absence of cats in the manifold ought make no difference to their reading. To be clear the job of the 'maniverters' is to raise exhaust temp so the performance of the main cat from cold is far better. Removing the maniverters will only delay the main cat in reaching optimal temp, it will just take longer. So its possible as long as you have an efficient main cat that will drop the O2 content sufficiently to hit the expected final lambda reading.

This also meshes with supersprint's advice that you will not suffer engine light with their product.

U should ascertain your current readings as well..

If you want to test at minimal cost, after ascertaining that it is the 'maniverters' that are broken/clogged, suggest u try the broom stick method and smash out the manifold cats, get as much of it out..... bolt it back up and if there is no MCSF, ur good to go.

http://www.supersprint.com/USP000ar15610.asp


u don't have to go the full manifolds, u can get cat replacement sections that bolt up if the stock primaries are fine as so:
http://www.prodigymotorsport.co.uk/catalog/images/supersprint/753611.jpg

or alternatively being mild steel a good exhaust shop may be able to cut out the two cat canisters in the downpipes and weld in some straight pipes...

iffin' it was me, full SS manifold for 600 euro is a steal.

[ForzaSab]

It turns out that one of the primary cat's has bitten the dust with all the honeycomb insides starting to fall apart.

I am able to get the two primary cat's from Sydney for $500 with sensors included but was wanting to have someone check it out before i go down that path.

Naturally my mechanic and the person selling the cat's said that you do need them or the car wont run, less money for them
Anybody have any tips on any muffler places in Brisbane that have experience with Alfa's?

[L4OMEO]

North or Southside? I've recently had a couple of places recommended to me by someone whose opinion I'd rate - CES (Custom Exhaust Specialists, I think it stands for) somewhere down Logan way, and Fat Pipes up in Kallangur. Haven't used either myself though.

Cheers
Rory

[ForzaSab]

I'm on th southside.
I've found a few places that seem reputable, yours was one of them Rory so cheers for that!
I've shot them some emails so i will let you know how i go should anyone have the same issues as me down the track.

[wankski]

I am able to get the two primary cat's from Sydney for $500 with sensors included but was wanting to have someone check it out before i go down that path.

Naturally my mechanic and the person selling the cat's said that you do need them or the car wont run, less money for them

whoa, $500 for what exactly? used items? what sensors? the actual lambdas... i am very sus over that price as the OEM lambdas themselves are around 80 quid ea for the jts...

whole thing new/used?

[ForzaSab]

The $500 was for the two primary lambdas (cat's) I hope i got the name right! lol
Just so I am on the right page as you wankski, the lambdas in the picture above (no.13) are in fact the primary catalytic convertors.
The two that i can get for $500 are secondhand, off a 2004 156 jts that had 34000 km's on it.
I've also shot an email to Cameron at Automotion so perhaps he can lead me in the right direction too.

[wankski]

ahh, i c! u might be a bit confused...

1) yes, those two canisters around item 13 are the 'primary cats' or 'maniverters'..

2) lambda = the 02 sensor that plugs into the cat. The bung where the lambda is installed is pictured only in the foremost cat pictured around item 13. (thing that looks like a circle at the top of the canister)

the lambda sensor looks like this:
http://cgi.ebay.com.au/BOSCH-LAMBDA-SENSOR-ALFA-ROMEO-156-2-0-JTS-16V-02-05-F2-/150493994957?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item230a241fcd#ht_5591wt_906

$500 all in for the entire section containing the primary cats is a decent price for the item...if for a lightly used item... IIRC the new alfa part is something around $3.5k....   

[ForzaSab]

OK it's taken me a while but i finally got the cat's changed on my 156, since getting a company car i haven't been driving it as much as i used to.

Anyway i'd like to give a plug and a stick it up your butt to two exhaust place's here in the Brisbane area.

I got a quote to get two Euro 2 catalytic convertors installed at Brisbane Exhaust's (Absolute Car Care) at East Brisbane, the price $1400.
They told me that the reason why it was so high is because they had to detach the water pump and that the cat's needed to be welded on, resulting with such a high labor cost.

I got a quote to get two "HI-FLO" primary catalytic convertors installed at Exotic Exhausts at Sumner Park, the price $800.
FYI i had the option for Euro 2 cat's at Exotic Exhausts also at a cost of $900 installed.
Simon at Exotic Exhausts was flabbergasted when i told him the quote from Brisbane Exhausts.

How the hell can Brisbane Exhaust wake up in the mornings with quotes like this?

Now i have a car that runs so much nicer, better response and better acceleration too!
I had some mechanics telling me that i'd be getting errors due to the faster rate of flow with the gases, this has not been the case.

Hope this helps you guys!!

[Alfapride]

thanks for the informative thread guys - glad to hear you sorted out your issue - from what I hear it seems this is a common problem on the model

[Art]

thanks for the informative thread guys - glad to hear you sorted out your issue - from what I hear it seems this is a common problem on the model

Hi All
Thanks for this useful thread. I have exactly the same problem with my 2005 156 JTS with 82k on it. One of the primary cats is causing an engine fault light. Probably caused by running rough before I got he camshafts changed due to abnormal ware! It seems to run OK, maybe a slightly odd/lumpy idle every now and then, but nothing else I can notice. I think I will also get the 2 primaries replaced with hiflo ones.
If anyone has any better ideas, let us know.
Art