How to find the exact catalytic converter for my 2004 Fiesta?

JackieChang

My Ford fiesta 2004 1.2 failed on emissions today. Everything else was fine. Time to get a new catalytic converter.

I entered my details on Mick's garage and it recommended this cat converter: https://www.micksgarage.com/d/catalytic-converters/ford/ford-fiesta/fiesta-2001-to-2008/1-25-16v-75-1242/products/1645644-4802-17703/bm-catalysts-catalytic-converter

A bit pricey, so decided to check eBay and found this: https://www.ebay.co.uk/itm/322551763839


Now the Mick's garage one says "Only in connection with: FK91187"

The one on eBay has "91187H" in the title.

Similar numbers. But I'm not 100% sure.

What else can I check to make sure I'm getting the right one from eBay?

Thanks

selectamatic

It's unlikely to be the cat tbh. It could be but it's generally the last thing to replace as it's the dearest fix and least common cause of emissions failures.

The lambda/O2 sensor could be faulty. The car mightn't have been fully warmed up etc.

Have you the exact results to hand?

fabsoul

Have you check https://www.autodoc.co.uk/
As i find they are a lot better that mick garage

JackieChang

selectamatic wrote: »

It's unlikely to be the cat tbh. It could be but it's generally the last thing to replace as it's the dearest fix and least common cause of emissions failures.

The lambda/O2 sensor could be faulty. The car mightn't have been fully warmed up etc.

Have you the exact results to hand?

Well the reason I think it's the cat is because I was driving with fairly bad misfire for a good few weeks. This was before I knew what a misfire was or that misfires were bad for the cat.

Anyway the mechanic who sorted out the misfire said I'm probably after ruining my cat. (which passed the NCT fine the previous year).

So that's why I'm 82% certain it's the cat.

Anyway, here's the emission results:


Low Idle:
CO 0.35 vol% (fails above 0.30%) MAJOR
HC 164ppm (fails above 0ppm) N/A

High Idle:
Lambda 1.02 (fails if not between 0.97 and 1.03) PASS
CO 0.44% vol% (fails above 0.20%) MAJOR
HC 114 ppm (fails above 200ppm) PASS


Everything else with the car is fine.

zg3409

Did you or mechanic read any error codes? Sometimes the car knows of an issue. You might get a new fiesta for the price of a genuine cat. It might make sense to get a used one from scrapyard, but I would ask mechanic to source and fit. Ideally use mechanic that has the equipment to measure emissions. As others have said its most expensive possible fix to emissions issue

sumo12

Cat will probably fix it for this years NCT, but the underlying problem will be back next year

Not sure if I'd be considering putting a new cat on a 2004 Fiesta

JackieChang

zg3409 wrote: »

Did you or mechanic read any error codes? Sometimes the car knows of an issue. You might get a new fiesta for the price of a genuine cat.

The error codes were misfire related when I fixed the misfire. The AA guy plugged in his OBD thing and said "misfire, cat is gonna be fecked" etc. after I told him I as driving it with a misfire for so long.

Although I have one of the OBD thing scanner things myself. Will check it out when I go home.

I'm looking at about €300 to get the cat replaced. Including parts (that ebay one) & labour (guts of €200 according to the mechanic).

Really don't want to have to buy a new car. I only use it for a 15 minute commute to work or to do a bit of shopping.

Bmw123d

JackieChang wrote: »

The error codes were misfire related when I fixed the misfire. The AA guy plugged in his OBD thing and said "misfire, cat is gonna be fecked" etc. after I told him I as driving it with a misfire for so long.

Although I have one of the OBD thing scanner things myself. Will check it out when I go home.

I'm looking at about €300 to get the cat replaced. Including parts (that ebay one) & labour (guts of €200 according to the mechanic).

Really don't want to have to buy a new car. I only use it for a 15 minute commute to work or to do a bit of shopping.

I’d also be going with there’s prob a a under lieing issue of the car running reach of lean. Secondly I would buy anything off mick garage possibly the dearest place to shop. Ah half decent mechanic should be able to sort that without needing a cat but fix both sure and ya know your good to go. I would hazard a guess the same cat on 1 or 2 other car brands

Del2005

Bmw123d wrote: »

I’d also be going with there’s prob a a under lieing issue of the car running reach of lean. Secondly I would buy anything off mick garage possibly the dearest place to shop. Ah half decent mechanic should be able to sort that without needing a cat but fix both sure and ya know your good to go. I would hazard a guess the same cat on 1 or 2 other car brands

Pumping unburnt fuel into a CAT will kill it, the OP pumped loads of unburnt fuel into theirs.

OP if the car is otherwise sound then spending €500 is a good investment for the use you make of the car, there's no guarantee that any car you get to replace it won't have issues no matter how much you pay.

JackieChang

Del2005 wrote: »

Pumping unburnt fuel into a CAT will kill it, the OP pumped loads of unburnt fuel into theirs.

OP if the car is otherwise sound then spending €500 is a good investment for the use you make of the car, there's no guarantee that any car you get to replace it won't have issues no matter how much you pay.

Correct I'm 95% certain it was the misfiring that screwed the cat.

I remember it misfiring as I was blasting down the motorway. Suddenly I couldn't make it past 50kmph in speed as the misfire got so bad. Had to get off the motorway and limp home via the back roads. Then called the mechanic to have a look and he said yep, you've most definitely ruined your cat. Especially since it had been misfiring for weeks before that. It just got really bad the day I went on the motorway.

There was literally nothing else wrong on the NCT cert. I think spending a few hundred sorting new cat would suit be better than getting a new car.

Now, my qestion in the OP. Any chance you are any good at finding the right part? I'm pretty certain I've found it, but need to be 100% sure.

greasepalm

Driving it for weeks even with a cat as 0.2 is a hard reading to achieve if engine is worn,Were new plugs,leads,coil pack and oil and filter done as oil will have petrol in it.Was the car driven hard before the test or just up the road.

JackieChang

greasepalm wrote: »

Driving it for weeks even with a cat as 0.2 is a hard reading to achieve if engine is worn,Were new plugs,leads,coil pack and oil and filter done as oil will have petrol in it.Was the car driven hard before the test or just up the road.

After the misfire, I installed new plugs and leads and coilpack. Misfiring stopped after that. I did not change oil, mechanic didn't tell me to.

Car was driven about 17km on a motorway to the test centre. It wasn't driven hard. Just regular motorway speeds. Car gets to about 3.5k revs at that speed.

Do you think an oil change and a good hard spin to the NCT might fix this? Like drive all the 17km in 3rd gear or something.

greasepalm

He should have told you to change oil and filter and maybe try a cat cleaner in fuel tank to see if it does lower your readings down before spending out on a new cat.Can your mechanic do exhaust test after 4 days of driving to see if you have to get a cat?

Plenty of people will say rally your car to get rid of the crap inside exhaust after oil and filter changed.

We had a toyota yaris diesel could only drive in limp mode and only used for short journey and the smoke it through out was horrendous.
threw in a can of fuel cleaner and 30 kmh was its limit and took it out on the road got it up to 70 kmh and less smoke.
Egr issue fault code and possibly done in 2 dpf on car,+wobbly crankshaft pulley and water pump issue =Too costly for repair.

SCOOP 64

My 98 Astra G 1.4 petrol Failed NCT on emissions
High idle CO 0.68 above 0.30 Failed
Low idle 0.50 above 0.50 Passed (just)
was thinking new cat also because done full service in June, after a month car running rough,only running on 3 cylinders,thought end of road this car, turned out to be faulty new spark plug, so when it failed nct thought i done damage to cat, any way passed nct last week, low idle vacuum leak, spilt pipe, high idle,replace egr valve, as code would come up now and again, also ran car on Dipatane for 2 weeks prior to test, a good hard one before test about a hour, point is don't assume cat as i did was just going to buy a new one but didn't ,check everything else first.
retest
low idle on 0.39
high idle 0.26.

JackieChang

I just read the error code using a device I have.

The only error code on the engine is:

"P0420 Catalyst system efficiency below threshold (Bank 1)"

greasepalm

https://www.fixdapp.com/blog/p0420-ford

was there a light on dash also?

JackieChang

greasepalm wrote: »

https://www.fixdapp.com/blog/p0420-ford

was there a light on dash also?

Yes the light and this code has been there for a while. I remember seeing p0420 before. The mechanic warned me about this problem after I drove with the misfire for so long.

I always suspected the cat was fecked, but wanted to wait until the NCT. If it passed emissions, I'd leave the cat there. If it failed, I'd change the cat. It failed.

So do you still think I should change the oil & filter, add some cat cleaner, run it hard, and maybe pass the re-test?

Or should I bring it to a mechanic so they can confirm the cat needs to be replaced. (and not something else)

What would you recommend now as you're obviously handy with cars.

greasepalm

Get oil and filter changed first and throw some catacleen into fuel tank if 1/2 tank or lower and drive it for a few days .Does your mechanic do emissions testing then get him to check it after a few days before you go back in .

JackieChang

greasepalm wrote: »

Get oil and filter changed first and throw some catacleen into fuel tank if 1/2 tank or lower and drive it for a few days .Does your mechanic do emissions testing then get him to check it after a few days before you go back in .

I'll give it a go. Could work.. and much cheaper.

I know a mechanic who can do emissions testing. If it fails, then what? New cat?

greasepalm

You can run diagnostics on car before you go to your mechanic and see if the fault code has come back,i presume you cancelled it and erased it.If after a number of days its still coming up expect the cat to be gone.