[kachamohan]

Thanks mate. Good to hear that red rage is back on road

Today after your confirmation, took blue bolt for software update and everything was done in <2 hours.

However the password was a little complex and I tried to change the SSID and password from the engineering menu, but couldn't. There's an option to modify, which takes you to a entry screen, with an update button. But the update doesn't really happen. Stays with the default SSID and password.

Actually, i tried this Wi-Fi option even before this software update and changed the password at that time. So, after the Android Auto got updated, I could still use the password that was set previously.

[padmrajravi]

What worries me more than the instances of engine power loss is that there is no root cause yet. I am afraid, they just delivered the car after an ECU reset or something. You need to escalate this at different levels to get a root cause here. Power loss in the middle of a run can easily cause accidents. For such abrupt shutdown instances, shouldn't there be error codes and logs in the ECU?

And for now, If I were you, I will assume the demon that caused the power loss is still out there till a proper explanation is given. It will be there on the back of your mind, every time you take the car out till the root cause is found. I also think the leak will appear again. I had a similar issue in my previous car where the leak happened only when the tank was full. Eventually, the whole fuel tank was changed under warranty. But I never faced such abrupt power loss because of it.

[Mudhalaipatti]

Day 3 after the fuel leak and engine power loss issue and there's still radio silence from ASC and from Mahindra, on the root cause and the fix.

If anyone has contacts within Mahindra who could be honest about this issue, please PM me.

[VW2010]

Sorry to hear your painful experience so far. I am starting to think you got a lemon and your misery is not going to stop anytime soon. I know I may be too early but the pain you are going through is not something I would pay for. M and M should take this as lemon and replace you with a new car. They already did for one and as with any other first version of Mahindra, it looks like a crappy product released without complete testing. Disheartened to see someone plonk their hard earned money and not having a peaceful first year of ownership.

[PrasannaDhana]

Originally Posted by VW2010

Sorry to hear your painful experience so far. I am starting to think you got a lemon and your misery is not going to stop anytime soon.

Woah woah! Hold your horses mate.

There are frequent issues in the car, but calling it a lemon is judging it too soon and too hard.

Replacing it with a new car is not going to be possible as Mahindra will find numerous reasons to avoid that scenario.

What he can hope is for effective resolution of these issues by Mahindra team.

This ownership thread can become an example of Mahindra resolving issues for their customer who has spent 20 lakhs in their product. I hope it doesn't become an example that's in the contrary.

@Mudhalaipatti, don't stress on regretting the purchase. Reach out to Mahindra as strongly as you can to resolve the issues.

Sadly, any Tata/Mahindra new launch is prone to niggles and their first batch customers have to shoulder the burden of being guinea pigs.

[VW2010]

Woah woah! Hold your horses mate.

There are frequent issues in the car, but calling it a lemon is judging it too soon and too hard.

I would not have called it a lemon if it were simple niggles like rattling etc. A car stopping suddenly, engine losing power, fuel leaking, hand brake not really working, and it being a Mahindra product i can take the leap of faith and start looking at if this was a lemon from the factory line

These are not small niggles.

[Mudhalaipatti]

Oh no. I wouldn’t call this a lemon. This is a brilliantly engineered product (call it ownership bias). Having owned a XUV500 before, I know first hand about niggles and issues with Mahindra cars. Compared to that that, XUV700 is fantastic, which I had indicated a few times in my ownership thread.

What I’m not really happy with, is the lack of focus and commitment from ASC and partly Mahindra on identifying and resolving this issue. ASC is trying to move on, now that the issue has disappeared. I don’t think they understand the seriousness of the vehicle loosing engine power, when you are on highway speeds.

Also why did the fuel leak in the first place. I had filled fuel the previous day and driven around 40km before fuel started leaking. And that’s why I’m not accepting this fuel air lock theory.

After I posted the previous message, called up the CCM to see if he has got any updates. Apparently the AGM had some personal issues and couldn’t arrange the vehicle to be picked up today, as they needed to work with Mahindra techs is identifying the root cause.
All I wished for was active follow-up and reassurance that Mahindra and ASC are not trying to sweep this issue under the carpet.

And looks like Mahindra is reading this thread. Got a call from the TN regional sales head and he promised that the vehicle would be picked up today and will be put through a thorough diagnostic and I will be provided with an update. In the meantime I would be provided with a donor to ensure mobility.

[ph03n!x]

Originally Posted by VW2010

...
I am starting to think you got a lemon and your misery is not going to stop anytime soon. ...

Woah! Ain't that a bit excessive?! You should also call all EPC issues, rattles, check engines, brake failures as lemons then, mate!

Not at all undermining the issues faced by @Mudhalaipatti - but let's face it, this is a trade-off for buying a car at launch prices, and this is from a Thar owner from Nov '20.

Originally Posted by PrasannaDhana

Woah woah! Hold your horses mate.

There are frequent issues in the car, but calling it a lemon is judging it too soon and too hard.
...
...
Sadly, any Tata/Mahindra new launch is prone to niggles and their first batch customers have to shoulder the burden of being guinea pigs.

Not just the Indian duo - this seems to be with everyone else too. The flip side is M&M is pretty responsive!

Originally Posted by Mudhalaipatti

Oh no. I wouldn’t call this a lemon. This is a brilliantly engineered product (call it ownership bias). ...

My 2020 MY Thar has had more than a dozen service actions so far - 2 issue actually bothered me, none left me stranded.

But I don't have to tell you this - your 5OO experience will tell it's a mechanically sound product, it'll all the new electronics and gizmos. Keep up the communication with M&M directly. Having an experienced MASS will definitely make it easier - half the issues get sorted here.

Let me know if I can help with M&M connects, am sure M&M is even more eager to ensure issues are sorted with the 7OO, it's their flagship!

[pta320]

The cost cutting is so much these days that car manufacturers are using cheap and inferior quality parts in the cars even in the critical systems.

I always wondered how can Mahindra offer so much for the price. The answer is here, the quality of parts and electronics used has gone down the toilet. Let's see if the later year models fix this issue or not.

And fuel leak from a brand new car is simply unacceptable.

I am yet to come across any series of problems or issues in Innova Crysta or Fortuner. Looking at issues in new XUV700, I am suspecting this car isn't for those who are planning to keep the car beyond warranty and possibly more than 10-15 years.

I really wished Mahindra, a true make in India and Indian brand would revolutionize the SUV segment, but it seems like things are going south.

[Bazooka]

Sometimes rat bites can induce strange behaviors. Have you checked that? If not, see if any wires are chewn in the engine bay.

[souvik6]

Originally Posted by pta320

The cost cutting is so much these days that car manufacturers are using cheap and inferior quality parts in the cars even in the critical systems.

I always wondered how can Mahindra offer so much for the price. The answer is here, the quality of parts and electronics used has gone down the toilet. Let's see if the later year models fix this issue or not.

And fuel leak from a brand new car is simply unacceptable.

I am yet to come across any series of problems or issues in Innova Crysta or Fortuner. Looking at issues in new XUV700, I am suspecting this car isn't for those who are planning to keep the car beyond warranty and possibly more than 10-15 years.

I really wished Mahindra, a true make in India and Indian brand would revolutionize the SUV segment, but it seems like things are going south.

I have to disagree with this statement having owned vehicles from Toyota, Honda, Audi, Hyundai & Mahindra over the last 20 years.

There is no evidence to suggest that Mahindra is using sub par components, on the contrary the sheet metal & structural integrity is on par if not better than the other makers, so is the engine performance & reliability.. sure they have collaborated with bosch & visteon for the tech stuff, still there is no compromise in quality as they are both global suppliers with decades of experience to multiple OEMs. There are software integration issues which are present however which could be fixed over time with updates.

It is wrong to generalize saying the product is subpar when having owned the xuv700 for 2 months I couldn't be happier with the revolutionary product launched by Mahindra in terms of safety, performance & tech innovations for the segment. This is not just my impression but the general consensus for the product.

Sure the product could have been tested more for software compatibility but mechanically the product is as good as one can expect at launch with very minor niggles in some cases.

I am not sure if you have long term experience with the car to confirm that the company is going South but I can assure you there is no cost cutting on critical components, there are however many improvements which could be done in terms of quality of plastics used and some basic features missed out on which in no ways compromises the performance of the machine.

Every car could face these issue especially if you expect a new product to revolutionize a segment. Every manufacturer globally has cases like these from Teslas to the Germans.

I don't think I have a bias towards Mahindra, I was myself very critical and unsure of xuv700 until I took delivery of the car. Although I have only done 600km so far I have enjoyed every minute of it and am just sharing my opinion.

I am very interested to know with specifics why you feel this way towards the xuv700?

[Mudhalaipatti]

After almost 4 days at the SC (1 day was pure rest, owing to a Sunday), the Red Rage is back in action. It looks like this issue had reached some of the top execs at Mahindra and I was glad my email to Syed Abdul Hanif at Mahindra had spurred further action.

I was driving a loaner Marazzo for the last few days and getting back, behind the XUV was such a welcome relief. Boy I missed driving this beauty. Even after 4 months of driving, the pleasure of driving is compounded every day. Only now, I have this incident lingering at the back of my mind.

Now lets retrace the sequence of events, leading up to the engine power loss last week.

1-March-22 - At exactly 2.33 p.m, I fill 43.16 litres of petrol, after driving for about 4 km post the low fuel warning. ODO is 4654 km.
I always stand with the attender to make sure that the fuel top up is stopped at cutoff. Not a millilitre more or less. Drive around 22 km and call it a day.
2-March-22 - It's a hot day and my lazy bum doesn't move the car to a shade and the vehicle is baking till 2.30 p.m. I take it out and drive for exactly 17 km and keep the vehicle idling for around 18 minutes, before I noticed the fuel leak at around 3.18 p.m.
2-March-22 - I take the vehicle to the SC and the rest of the story is documented in this thread. Now there is a detail that I didn't think was unusual and I missed to report earlier, but here I am retracing the steps and think this could be key to the whole saga. As the flashing is completed, the Co Tech cranks the car, but it doesn't start. He tries at least 6 times, but the vehicle doesn't crank. And then on the 7th time, the vehicle starts. I didn't pay attention to this specific issue, but in hindsight, this is a pivotal moment.

Central to this drama is the EVAP system (Evaporative Emission Systems). What is this EVAP really ? Here is an excellent video of how it works in modern cars.

https://www.youtube.com/watch?v=Wbv49SdhL2I

(There's a minor glitch at 5.50 where there's a bit of incorrect information. Read the comments for the right information, just for that tiny bit).

Had a longish call with the Area Customer Care Manager and he explains me in detail the diagnostic and the findings. I have given a gist of our conversion below.

The vehicle has a Canister, Purge Valve to handle the fuel vapour. (i.e in this BS stage VI regulation, no unburnt fuel can be let out and so all fuel vapour must be re injected in to the system, with out being let out in to the environment). In my case, somehow the canister, which is supposed to capture only vapour, had accumulated fuel, quite a bit. And then this accumulated liquid found it's way to intake manifold, which eventually let to the engine shutting down. Since there was lot of accumulated liquid in the canister, it started leaking out in the first place.

Now, if you had gone through the video and the explanation provided by Mahindra, you may find a number of questions arising, which is not very reassuring. But before I get in to my reservations, some replacements parts on the vehicle. Mahindra has replaced both the Canister and Purge Valve in my vehicle, due to "abundance of caution". They weighed my stock canister and a non problematic canister and apparently both weighed the same. If fuel had been absorbed by the charcoal, it would have weighed more. However since it was almost 3 days past the initial fuel leak, all the leaked/accumulated fuel would either have evaporated or been converted to fumes. Also some valuable logs had been lost during the flashing process (as part of the Android Auto Update )

Mahindra suspects that excess fuel was filled on 1-Mar, which might have seeped in to the canister that triggered the chain reaction. This is something that I can't accept. As I always fill fuel at cutoff and in this instance, the low fuel warning had come off just a few km earlier and so there's almost 0 chance of overfilled fuel causing this.

Even if that was the cause, how did liquid get accumulated in a canister, which is supposed to capture only vapour. Isn't there a sensor/valve to let in only vapour ?

How did the canister accumulate so much liquid and how did the canister leak fuel. Was it via the canister vent value ? If that's the case, is it designed to spill fuel all over the wheel well, with out a proper "Drain"/"Vent" mechanism ?

And the most serious of the issue - The purpose of the Purge Value is to let in only vapor in to the intake manifold and that too when the conditions are "right", as decided by the ECU. A vehicle with so many ECUs, determined that liquid could be let in to the intake manifold from the canister ? How !!! How !!! How !!!

Even if all other fail safe controls failed, the ECU controlling the engine parameters, should have thrown out a "check engine" light at worst and not shut down the engine, especially when the vehicle is cruising at highway speeds. Where is the redundancy in the system ?

And now, the critical missing link (my version) - While the canister had accumulated fuel and the EVAP purge valve is injecting liquid in the intake manifold, the injected fuel is getting burned up fast, as the engine has been running continuously. However once the engine is shutoff while flashing is in progress, the fuel in the EVAP system is in fact clogging the intake manifold. That should explain why the vehicle refused to crank for 6 times. But again, the diagnostic tool was connected to the vehicle when the cotech was cranking up the vehicle and it should have spewed warning after warning, which I'm thinking were ignored.

And it must be pure timing, where the engine didn't stop on a good 15 mins ride that we took with the vehicle, right after the flashing process, but started a good 2 hours after. By this time, the fuel in the canister has dried up and whatever left over liquid in the EVAP system found it's way to the engine again, which stopped the engine.

My Summary

Vehicle baking in direct sunlight for a good 6 hours -> Fuel vapours form -> Some faulty sensors/valves let liquid fuel in to the EVAP canister -> Canister leaks liquid fuel out of the vehicle -> Canister leaks liquid fuel in to intake manifold -> Engine power loss.

While Mahindra is of the view that this is a 1 in a million occurrence, and is an outlier, I can't buy this argument, especially considering what happened. The engine shutdown, for gods sake! And that too with so many ECUs in place to monitor so many vital parameters.

Verdict

And now my verdict on this issue - Mahindra XUV700 has/had a problematic EVAP setup. I'm not sure if it's just my vehicle of it's to do with a particular batch of vehicles and I can't pin point which part of the EVAP system is at fault (perhaps some solenoid, some sensor, some piece of software idk). This demands a more thorough diagnostic with a larger dataset. With many vehicles onroad, Mahindra should be able to get a much wider dataset to ascertain if there's a real issue with their EVAP setup or not. I wouldn't wait for a fatal incident to revisit this topic !!

Silver Lining

Mahindra has been cooperative and forthcoming in this whole saga, with keen attention to solving the problem. However in this case, the critical logs/data points to get to the bottom of this was lost in the SC goof up. I understand that a whole team of Mahindra Technicians were on this task trying out a lot of permutations and combinations. Their interactions with me very courteous and conveyed their earnestness in resolving this issue. I'm sure with more data points, this issue could be rectified ( if at all this is a wider issue)

I would be extremely glad if you guys could pick holes in my theory, my summary and verdict. I hate to draw this verdict on such a great piece of engineering and would love to be proved wrong.

In the meantime, I'll try to put this out of my way and enjoy driving as much as I can and should.


PS : I almost forgot. There's no trace of a rat/squirrel or a cheetah infestation in the vehicle. And so something with sharp teeth having fun with tubes and pipes is ruled out.

[pta320]

Originally Posted by souvik6

I have to disagree with this statement having owned vehicles from Toyota, Honda, Audi, Hyundai & Mahindra over the last 20 years.

There is no evidence to suggest that Mahindra is using sub par components, on the contrary the sheet metal & structural integrity is on par if not better than the other makers, so is the engine performance & reliability.. sure they have collaborated with bosch & visteon for the tech stuff, still there is no compromise in quality as they are both global suppliers with decades of experience to multiple OEMs. There are software integration issues which are present however which could be fixed over time with updates.

It is wrong to generalize saying the product is subpar when having owned the xuv700 for 2 months I couldn't be happier with the revolutionary product launched by Mahindra in terms of safety, performance & tech innovations for the segment. This is not just my impression but the general consensus for the product.

Sure the product could have been tested more for software compatibility but mechanically the product is as good as one can expect at launch with very minor niggles in some cases.

I am not sure if you have long term experience with the car to confirm that the company is going South but I can assure you there is no cost cutting on critical components, there are however many improvements which could be done in terms of quality of plastics used and some basic features missed out on which in no ways compromises the performance of the machine.

Every car could face these issue especially if you expect a new product to revolutionize a segment. Every manufacturer globally has cases like these from Teslas to the Germans.

I don't think I have a bias towards Mahindra, I was myself very critical and unsure of xuv700 until I took delivery of the car. Although I have only done 600km so far I have enjoyed every minute of it and am just sharing my opinion.

I am very interested to know with specifics why you feel this way towards the xuv700?

There is no long term experience for XUV700 as the product is very new.
But looking at the discussion here, I am seeing more than usual niggles and failures for this car.

I don't wanna hurt the sentiments of the owners who have put their hard earned money on buying XUV700, I am just a bit more critical about these things. The first thing that comes to my mind when buying a car is how long it's gonna last without costing me a small fortune on repairs. And looking at the initial issues here, I am quite convinced that post warranty, the niggles will increase and will cause a dent on your wallet. I am also very critical about VAG cars as they also tend to have such kind of problems and cost a fortune to maintain post warranty. Being honestly critical about a product will in some way or the other push the manufacturer to look into rectifying the issues for the future models. If you feel something is wrong, speak up.

Now everyone has their own preference when buying cars, some want to keep it only till the warranty lasts, some want to keep it for 15-20 years, me being amongst the latter and value conscious person, always want to put money on the product that won't let me down with expensive repairs. If you belong to the other group and have lots of funds, by all means go ahead and get your dream machine.

What I am expecting is in the later model years, Mahindra will hopefully improve the niggles and complaints. I'll stress it to the point that prospective buyers who CAN wait SHOULD wait for at least one year and not rush right now for the XUV700, or if you cannot wait, settle for the lower spec model. In the long run, it will be worth the wait.

It's a not a car that will set you aside with some nickel and dime repair but is a very complex vehicle with many computerized parts. An electrical problem in such a car will be a nightmare to fix once the warranty is over. Just look at complex Mercs or BMWs, many people get rid of the car post warranty, and rarely average people keep such cars beyond 8-9 year mark, the answer is that most electronics starts to break post that window. And XUV700 has features that even beat the BMWs and the car costs a fraction, the math speaks itself about what to expect if the issues are not rectified from the factory.

[venkyhere]

Originally Posted by Mudhalaipatti

My Summary

Vehicle baking in direct sunlight for a good 6 hours -> Fuel vapours form -> Some faulty sensors/valves let liquid fuel in to the EVAP canister -> Canister leaks liquid fuel out of the vehicle -> Canister leaks liquid fuel in to intake manifold -> Engine power loss.

While Mahindra is of the view that this is a 1 in a million occurrence, and is an outlier, I can't buy this argument, especially considering what happened. The engine shutdown, for gods sake! And that too with so many ECUs in place to monitor so many vital parameters.

Verdict

And now my verdict on this issue - Mahindra XUV700 has/had a problematic EVAP setup. I'm not sure if it's just my vehicle of it's to do with a particular batch of vehicles and I can't pin point which part of the EVAP system is at fault (perhaps some solenoid, some sensor, some piece of software idk). This demands a more thorough diagnostic with a larger dataset. With many vehicles onroad, Mahindra should be able to get a much wider dataset to ascertain if there's a real issue with their EVAP setup or not. I wouldn't wait for a fatal incident to revisit this topic !!

@mudhalaipatti

I think what must have happened was a 'stuck closed' vent valve (manufacturing defect, poor robustness against dust/debris etc) - allowed huge positive pressure to build in fuel tank and the canister (purge valve closed when vehicle off) - whist your car was baking in the sun for long hours. Then as you drove off, the moment purge valve opened, the "sucking" from intake manifold was super high (mega positive pressure that got built up, suddenly released by purge valve opening) due to the massive pressure gradient, that not just vapours, liquid fuel got pulled in, into the canister. And even after the canister was soaked with petrol, the pressure gradient (b/w the intake manifold and fuel tank) was still there to 'suck in' the liquid itself.

Valves can't behave 'liquid only' or 'gas only' they are just opening/closing a path inside a tube. So the puge valve (poor thing, it was only faithfully doing it's job) is not at fault.
However, the MAP sensor or TMAP sensor within the intake manifold should have fired/set a warning/error code or made the vehicle go into limp mode, before even you went to the M.A.S.S for the software update. I am surprised this didn't happen.

I am also surprised that the BCM(or PCM) didn't 'detect' that the vent valve is faulty. Other than the vent valve being faulty and allowing a massive pressure build up inside the fuel tank, I simply cannot imagine how liquid would get sucked into the canister at all. From the time the car was baking in the sun, and until you cranked the car up and ran a little bit until engine reached operating temp and the purge valve opened, the canister wouldn't have had anything other than vapours (high pressure vapours) , but the moment the purge valve opened, vapours, liquid fuel, everything, got pulled in, very violently.

[Mudhalaipatti]

Thank you @venkyhere. That explanation fits perfectly in the scheme of things. Bhpian @impala faced a similar issue as well.

And so, the vent valve is stuck, allowing massive buildup of pressure and the when the sensors decide to open the purge valve, everything from the fuel tank gets sucked in, in a violent tornado, leading up to engine power loss. And so Mahindra's service advisory asking customers not to fill to the brim is either ill advised or diversionary or both.

A pattern is emerging now, i.e this seems to happen the day after the tank is filled/after certain km being driven. Lets see what others have to report.