[shrvenkataraman]

Got a tiago bs4 2020 jan xz version.

Recently got engine light symbol for a while and tata showroom reset it

It turned up again and they checked and they are saying it's a catalytic converter failure and that replacement would cost 30k+ and that they have to order the part.

Is this right? Do catcons fail in under 50k kms? And do they cost this much for tiago? In december I remember the workshop person saying 10-12k estimate and now suddenly it's 30k.

Car is at tata techwheels workshop in Jaipur sitapura. They are saying it will take 5-6 days for part to arrive.

What are the odds of catcon failure under 50k kms of mileage? And how do I find out what the actual cost of catcon is - and if tata is not having me overpay for it?

[suhaas307]

Catalytic converters are generally very expensive, since they are packed with several precious metals such as palladium, rhodium, etc.

Normally, it is expected to cost upwards of 50k. Not sure what Tata charges for a replacement cat-con but I do not expect it to be cheap at all.

Please check with multiple dealers / authorised service centres.

Failure in 5 years / 15,000 km could be considered premature. You must press your dealership / authorised service centre to replace it at their cost or at a discounted rate at the very least.

[GaryTSI]

CatCon failure under 50k kms seems very strange, almost impossible dare I say. Catalytic Converters can easily last over 10-15 years and upwards of 2 lakh kms if maintained properly. I would advise you to check this with another Tata Service Centre or an FNG to get various opinions and ensure it has been properly diagnosed.

The problem may lie with a faulty O2 sensor which is more known and prone to such issues hence the Check Engine Light, either way, it's easier and more cost-effective to rule out the smaller possibilities rather than jumping to an expensive solution that isn't even certain to fix the error.

[aj_]

Also, if the catalytic converter has gone bad this early, it means that there is some problem with the combustion in your engine.

In that case even if you get the catalytic converter replaced, it will again fail in the future, so it's better to ask them to inspect that why the catalytic converter has gone bad this early, repair the actual fault first which is probably related to combustion then only replace the catalytic converter.

[shrvenkataraman]

They said they'll have to keep the car for 5-6 days, i asked for it back until part arrives. They returned the car with 3 scratches below headlight. :-|

They basically mentioned that as a policy tata doesn't repair catcons because repair only means cleaning of the catalytic converter and if the cleaning is not thorough and even small amount of dirt or impurities remain inside that it will cause fault again.

They mentioned that it may be done aftermarket and that I'd have to contact someone who does it aftermarket, but even if it is done, there's a high risk of failure again. So they advise me to go for brand new catcon.

I am not a car guy, a software engineer here. So, I don't really understand these things and I try to read about all this. Not sure what's the next step here other than to wait for the catcon part arrival.

This was the error code diagnostic that they shared.

https://www.team-bhp.com/forum/attac...724873&thumb=1

[Doge]

Like AJ mentioned, such an early failure of cat con, if that's what actually happened is quite worrying and may be a symptom of a much more serious engine issue. You need to get it checked by a good FNG, check the teambhp directory for one and get a second opinion on this.
Also email some higher ups at Tata, asking how is it possible for the cat con to fail so early and question their poor quality.

[wheelspinner]

Originally Posted by shrvenkataraman

Got a tiago bs4 2020 jan xz version.

What are the odds of catcon failure under 50k kms of mileage? And how do I find out what the actual cost of catcon is - and if tata is not having me overpay for it?

No, they don't fail that early. Based on what you narrated, have you explored the possibility of theft of the precious metals in your catalytic converter? This is not impossible and happens if you leave the car unattended at mechanic's place. The mechanic might sell it, and stuff junk inside it. Then after a few driving cycles, you will get the check engine light.

[aj_]

Originally Posted by shrvenkataraman

This was the error code diagnostic that they shared.

This is weird, because if you look at the fault code, it says memorized and not current.
Please read the points below:

Current fault code (active code):
This is a code that is triggered when the vehicle's computer detects a malfunction happening right now, usually causing a warning light to be illuminated on the dashboard.

Memorized fault code (stored code):
This is a code that was previously detected by the vehicle's computer and stored in memory even if the problem has been fixed, meaning it can be viewed later through a diagnostic scan.

Ask them to clear the fault codes and see if it comes back again.

[shrvenkataraman]

Originally Posted by wheelspinner

This is not impossible and happens if you leave the car unattended at mechanic's place. The mechanic might sell it, and stuff junk inside it.

So far all our services have been with an authorised tata service center. Is it possible that such theft could happen at Tata authorised service centers also? And how do I actually verify that this could have been the case?

[sagarpadaki]

Originally Posted by shrvenkataraman

So far all our services have been with an authorised tata service center. Is it possible that such theft could happen at Tata authorised service centers also? And how do I actually verify that this could have been the case?

In case of theft, the catcon will be hollow. It will not have any honeycomb structure inside. Since catcon is expensive, I suggest you remove it from the car at an FNG, and clean it yourself. All you need is water and liquid detergent. There are many videos on YouTube on how to clean catcon. If even after cleaning and drying, the issue persists then you can think about replacement.

[aj_]

Looking at that code being in memorized state, it feels more like a wiring issue to me rather than catcon, if you know about cars, P0420 code is very notorious and is very difficult to find the cause of the issue. To me it looks like wiring to some sensor which is involved in intake/exhaust might be cut open and shorting with ground via body of vehicle and its causing this.

[shrvenkataraman]

They actually cleared the fault code once and it came back. And then they reset it again.

[saitvsk23]

Originally Posted by shrvenkataraman

They actually cleared the fault code once and it came back. And then they reset it again.

Please try replacing the O2 sensor. Generally, in most cases, P0420 code is attributed to a bad sensor. I own a Camry, and in most cases the sensor goes bad. In Camry it is of Denso make, I dont know what Tata uses. I'll put up an image of it here. They should be able to take out the O2 sensor, spray a lot of brake fluid onto the sensor part, and screw it back. If the issue goes away, then well and good. If not, replacing the sensor will not hurt either. This should mostly solve this issue.

Again, the service center guys will refuse to do any of this saying warranty will be voided saar and all. Dont listen to them. Take your car to a good FNG. This is just a sensor and does not compromise the warranty in any way.



The screw like part screws into the exhaust manifold, just before the catalytic converter. If the sensor gets clogged due to all the exhaust gases passing through it, it often reads a bad signal and sends the same to the ECU. The ECU reads it as a problem and puts up a check engine light.

This should solve it for most of the cars.

BUT, INCASE :

If you felt your car sluggish, read it as : if you're pressing the accelerator pedal and the car is not going like it is supposed to (I am not trying to be crass but think of it like the engine has constipation, its trying hard to make power but the car is not going ahead as its supposed to), then you might have to actually replace the catalytic converter.

This basically happens when the substrate inside the catalytic converter (the honeycomb like structure that one of the users was talking about) gets clogged up. Now, this might get serious.

In petrol vehicles, we all know that petrol burns up fully and does not leave any residue. But, oil on the other hand, leaves a gunky kind of residue when exposed to high temperatures. We might have come across the situation where the mechanic says "saar the car is burning/consuming oil saar". This basically happens when the piston rings go bad. Here, this gunky residue might get caught by the catalytic converter and clogs up the pores of the honeycomb substrate. If it is clogged, the exhaust gases cannot go out of the catalytic converter and the engine feels like its constipated.

I had the P0420 code on my Camry, and the ultimate solution was to replace the exhaust manifold. It comes as a single piece, the manifold piping and the catcon unit. There was diagnosis done and it resulted in a clogged catcon. I was aware that my car had oil consumption issues, but I didnt know that it was this bad.

There is a likely fix to this as well. If this issue comes up in high powered vehicles (4 cylinder and 6 cylinder engines) and the vehicle does not feel sluggish yet, just take it on a long stretch of a highway and floor the gas pedal. Keep the engine at high revs. That should clear out the catalytic converter and the issue should go away on its own.

[shrvenkataraman]

Originally Posted by saitvsk23

Again, the service center guys will refuse to do any of this saying warranty will be voided saar and all. Dont listen to them. Take your car to a good FNG. This is just a sensor and does not compromise the warranty in any way.

I don't think the car is under warranty. If i remember correctly, tiago has a 3 year warranty which for me expired by 2023 december. So, yes - it's out of warranty. But they did say they don't do repair of catcon and that they can only replace.

And, the workshop manager did tell me that catcon is failed most likely due to quality of fuel. I asked him "if quality of fuel has caused this, why are million others driving similar cars not reporting catcon failures under 20k kms".

Not once did he attribute it to poor qc at tata's end or anything else.

Anyway, I asked him to deliver the car back and he's given it back until part arrives. But going by all the comments here, I should first get my car to a decent FNG and check the root cause of this and then decide what to do. O2 sensor replacement should work theoretically. I'll update here once i have findings from a separate fng.

i'm from Jaipur. does anyone know a good FNG here in Jaipur?

[sagarpadaki]

Originally Posted by shrvenkataraman

I don't think the car is under warranty. If i remember correctly, tiago has a 3 year warranty which for me expired by 2023 december. So, yes - it's out of warranty. But they did say they don't do repair of catcon and that they can only replace.

Catcon cannot be repaired because there is nothing repairable inside it to repair. As an alternative, ask the service center to swap the cat con from a different tiago onto your car and go for a drive. If the catcon is indeed faulty, the car will not throw error with the swapped catcon. Offer to pay labor charge for this activity which anyway is far cheaper than a new catcon. Atleast you will have a proper root cause