Clubjazz - Honda Jazz & HR-V Forums

Honda Jazz Forums => Honda Jazz Mk1 2002-2008 => Topic started by: guest5196 on January 07, 2015, 08:31:32 PM

Title: Cheap aftermarket cats
Post by: guest5196 on January 07, 2015, 08:31:32 PM
Hi all,
Not mine and not literally stolen, but basically kwikfit told my mum she needed a new cat for some unknown reason (the car was running fine with no lights etc but had gone in for a new backbox). They put some cheap aftermarket cat on, chargef her £700! and the warning came on a day or so later. She took it to Honda who said the new cat wasn't up to the job, and so went back to kwikfit who said they'd refund her for the new cat but the old one had already been 'disposed' of....

Apprarently honda said a proper honda cat will fix the issue, but they are over 1k!

So can anyone help? Is it possible to decat a jazz without engine management or MOT issues? Or perhaps Honda are wrong and the cheap cats do work, but perhaps a new o2 sensor or ECU reset is needed? I'd be suprised if they forgot to rule out the latter, but perhaps they just wanted to sell her a 1k cat... You can't trust any garage these days!

I've had loads of mk2 crxs and an s2000 so I'm a big fan of Hondas and know a fair bit about mechanics, have an obd scantool etc, but unfortunately she lives a couple of hours away so ive not been able to check over the car myself.

Any advice appreciated!
Cheers

Edit 8 Jan 2015 by Admin - changed topic title to something more accurate.
Title: Re: Cheap aftermarket cats
Post by: culzean on January 08, 2015, 10:55:43 AM
Unfortunately a lot of garages prey on women drivers because they are easy pickings - garages have told my wife new stuff is needed but she quickly got wise and now asks me first.  They probably 'disposed' of the CAT to another customer :-X.

Personally I would run the car with present CAT and see if anything happens to fuel consumption etc. which would indicate Oxygen (lamda) sensor is not seeing correct exhaust gas result ( I think most cars now have two O2 sensors, and there may be one before and one after the CAT ??? )

My mate who is a mechanic says you can get a good Jazz CAT for about £200.

Edit 8 Jan 2015 by Admin - changed topic title to something more accurate.
Title: Re: Cheap aftermarket cats
Post by: guest334 on January 08, 2015, 03:20:46 PM
I would speak to Kwikfit again and ask them to put your Mum's car back the way it was, give them another chance to rectify then mention small claims court etc.
A quick search on E bay reveals many approved cats for around £120.00
http://www.ebay.co.uk/sch/Car-Parts-/9884/i.html?_nkw=honda+jazz+catalytic+converter (http://www.ebay.co.uk/sch/Car-Parts-/9884/i.html?_nkw=honda+jazz+catalytic+converter)

Edit 8 Jan 2015 by Admin - changed topic title to something more accurate.
Title: Re: Cheap aftermarket cats
Post by: degzi on January 09, 2015, 07:22:25 PM
Hmmm can't see any reason why a cheap cat won't work. On my old car I fitted a £50 one welded in, that sailed through MOT's after it was done.

Any car manufacturer will say it's not up to the job if it's not their brand.
Title: Re: Cheap aftermarket cats
Post by: guest5196 on January 10, 2015, 02:05:10 PM
Thanks for the replies.

I've said to take it somewhere else for a disanostic. Seems like its more likely to be a damaged/faulty sensor or an ECU reset needed.
Title: Re: Cheap aftermarket cats
Post by: guest4078 on January 11, 2015, 11:58:37 AM
I ran my pink peril ok with a 100 quid cat from the 'bay, as degzi did with his. I think they have either damaged or incorrectly installed a sensor and as you and Culzean says this could throw up a fault.
I agree with olduser1 I would be camping (tent type) at kwikfit until they fixed it. They are rubbish.
Title: Re: Cheap aftermarket cats
Post by: degzi on January 20, 2015, 02:22:38 AM
Just re read this, and I'm betting it is an o2,sensor too probably has been damaged or put in wrong etc.now if you have a multimeter take off the plug from the engine side and check resistance and stuff.

http://ngkntk.co.uk/index.php/technical-centre/lambda-sensors/how-to-test-lambda-sensors/ (http://ngkntk.co.uk/index.php/technical-centre/lambda-sensors/how-to-test-lambda-sensors/)

Just for the record don't pay over the odds for a sensor,same as a cat if it fits it fits the science behind it is the same.
I have also discovered that cleaning o2 sensors does work so if its showing a fault give it a light brush over and re-try it. But ask yourself if its covered in crap then why?

O2 sensor is your cars equivalent of a heart. If it detects too much variance it effects everything.
Title: Re: Cheap aftermarket cats
Post by: guest5196 on January 20, 2015, 10:54:06 PM
OK cheers for the tips, will update when I know more.
Title: Re: Cheap aftermarket cats
Post by: SuperCNJ on January 23, 2015, 06:40:09 PM
Funny you had this problem too. I literally had a new cat and front o2 sensor replaced on our jazz yesterday, at our local kwik fit!

Our car failed the MOT on emissions and was only something like 0.01g out but they wouldn't pass it. The replaced the rear o2 sensor, flushed the engine but same reading, then replaced the front o2 sensor and same reading, so it was a failed cat. Apparently it was actually the front o2 sensor failing making the engine run too rich and damaging the cat.

Anyway, they replaced it with an aftermarket cat which they assured me was the exact same cat that honda use, came from the same manufacturer and factory but branded differently. Only difference was the cost.

It was £480 all inc, but managed to negotiate it down to £450.

They actually did a good job, I've never had any work done at kwik fit other than MOT (cheap) as I never trust the mechanics there, but it seems they have started to get their act together as their new staff were very good.

The only thing is, there is an awful burning smell coming from the engine bay that hasn't gone away yet, I was told it was the new cat. Does anyone know if this is true or if this is something to be worried about? Does it go away?

Title: Re: Cheap aftermarket cats
Post by: Hobo on January 23, 2015, 07:07:10 PM
Could probably have saved £450 if you had not gone to Kwik Fit for an MOT, I would not go near them for anything they are notorious for doing work that is not needed, they told my daughter she needed new discs and pads for £350 when she had a vibration which turned out to be the ABS cutting in when she braked hard, she still had the same discs and pads after two more MOT's at independent garages.
Title: Re: Cheap aftermarket cats
Post by: culzean on January 23, 2015, 07:24:34 PM
Funny you had this problem too. I literally had a new cat and front o2 sensor replaced on our jazz yesterday, at our local kwik fit!

The only thing is, there is an awful burning smell coming from the engine bay that hasn't gone away yet, I was told it was the new cat. Does anyone know if this is true or if this is something to be worried about? Does it go away?


It is normal to have a burning smell for a short period after having any part of the exhaust replaced,  just the oil and plating on new part burning in.  The CAT does run very hot, and is far forward in the car,  so these fumes will find their way into car fresh air intake.  If the smell continues too long  (more than a couple of weeks) I would take it back to Kwik-Fit - last thing you want is exhaust fumes in the car,  but if any joints were leaking in that area it would make quite a loud blowing noise.
Title: Re: Cheap aftermarket cats
Post by: EY11 on March 17, 2015, 10:08:43 PM
I had a replacement aftermarket full exhaust system fitted by my local garage.

After about three weeks the engine management light came on and diagnostic came back with the code for Cat below efficiency or something along those lines.

They changed the cat and all was good for another three weeks but then the light came back on with the same fault code, sorry I'm not sure of the fault number.

Anyway it went back in today and there was a blow from the front olive which they have resolved and reset the fault code.

Anyway after fifteen miles tonight the light is back on.

What is the general consensus here, I am just unlucky and have a got a faulty cat or is it more likely that one of the O2 sensors has been damaged in the process?

Any advice great fully received.
Title: Re: Cheap aftermarket cats
Post by: culzean on March 18, 2015, 08:26:42 AM
There should be two sensors, one before before and one after CAT,  the upstream sensor checks 'untreated' exhaust gas and makes adjustments to mixture and the downstream one is there to check what is coming out of the CAT,  if CAT is not doing its job properly the downstream sensor may be throwing up a fault,  seems strange that error only appears after running for a few weeks though,  seems like CAT may be not doing its job properly or getting coated up inside after a few miles which stops it performing.  Problem is with aftermarket CAT's is that they often don't have either same quality or same amount of the required expensive metals and quickly coat up or simply just don't clean up exhaust enough to keep downstream sensor happy.

http://www.honestjohn.co.uk/askhj/answer/49870/use-genuine-catalytic-converters-not-aftermarket-ones- (http://www.honestjohn.co.uk/askhj/answer/49870/use-genuine-catalytic-converters-not-aftermarket-ones-)
Title: Re: Cheap aftermarket cats
Post by: EY11 on March 18, 2015, 03:29:01 PM
So should an aftermarket Cat be OK?

I'm not sure the original needed replacing but I had the whole exhaust system replaced as it had a couple of holes developing in it and given the age of the car elected to have it all replaced at once instead of in sections as they failed.

Car is 10 years old with 80K on the clock.

I'm hoping to keep the car for another 2-3 years but don't want to be in and out of the garage all of the time due to a faulty catalytic converter.

Exhaust has got a two year guarantee which I assume includes the cat as well.
Surely an aftermarket Cat should be good for at least a few years?
Title: Re: Cheap aftermarket cats
Post by: SuperCNJ on March 19, 2015, 06:41:12 PM
So should an aftermarket Cat be OK?

I'm not sure the original needed replacing but I had the whole exhaust system replaced as it had a couple of holes developing in it and given the age of the car elected to have it all replaced at once instead of in sections as they failed.

Car is 10 years old with 80K on the clock.

I'm hoping to keep the car for another 2-3 years but don't want to be in and out of the garage all of the time due to a faulty catalytic converter.

Exhaust has got a two year guarantee which I assume includes the cat as well.
Surely an aftermarket Cat should be good for at least a few years?

I had one fitted (see above) at kwit fit and the fitter told me that it is identical to the one honda use in that, it comes out of the same factory but doesn't have the honda branding.

No sure how true that is, but I have heard others say this before.

Title: Re: Cheap aftermarket cats
Post by: culzean on March 20, 2015, 05:40:22 PM
So should an aftermarket Cat be OK?

I'm not sure the original needed replacing but I had the whole exhaust system replaced as it had a couple of holes developing in it and given the age of the car elected to have it all replaced at once instead of in sections as they failed.

Car is 10 years old with 80K on the clock.

I'm hoping to keep the car for another 2-3 years but don't want to be in and out of the garage all of the time due to a faulty catalytic converter.

Exhaust has got a two year guarantee which I assume includes the cat as well.
Surely an aftermarket Cat should be good for at least a few years?

I had one fitted (see above) at kwit fit and the fitter told me that it is identical to the one honda use in that, it comes out of the same factory but doesn't have the honda branding.

No sure how true that is, but I have heard others say this before.

Probably not true,  car makers have strict quality standards for their suppliers parts and don't like failures in service which gives the whole car and the car maker a bad name,  they expect (example) a battery to last 5 years, a CAT to last >150K , an exhaust system to last 10 years etc. etc. 

Aftermarket exhausts are half the weight of an OEM system because thinner wall tubing is used,  the aftermarket unbranded CAT will have less active and lower quality oxidizing material in them - I have heard that scrap dealers will give good prices for OEM branded CATs (because of all the expensive metals in them)  but nothing for aftermarket ones.

Quote below from CAT manufacturers website. Basically CATS need to run very hot to work properly and oxidise exhaust gas efficiently, and just like a DPF frequent short hops without a motorway run or Italian tuneup will effectively cause them to block up and fail. Just another reason to avoid very low mileage (for their age) vehicles when buying secondhand. Puttering around below 2000rpm all the time is probably considered 'engine abuse' by Honda lovers all over the world.  Honda should put a 'born to rev' sticker on their engines.

Short journeys can contribute towards a short catalytic converter life. Unless the
vehicle reaches normal operating temperature (not necessarily as indicated by the
water temperature gauge) on a journey the converter will become blocked/
restricted and lead to premature failure.