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That is the wrong thing to do.

In an automatic or AMT never use your left foot. Use only right foot and handbrake to move the car. Please go through the owners manual and read how to drive in such cases.

Maybe since driving an automatic was new to you, you ended up burning the clutch by using this method. When the left leg is used for braking and right for accelerator, the clutch heats up pretty quickly, as quick as coming out of a basement in reverse. When I had left the car for alignment, one of their guys there had never driven an automatic before, and to remove the car from the alignment bay, which is actually in the basement of a building, used the brake to hold the car while he accelerated with his right foot. It overheated the clutch and when the car was handed over to me it had the TCM light blinking and a beeping alert.

The next time I went to get the wheels aligned, I took out the car myself and did not use the brake. At one point where I had to hold, I used the handbrake and this didnt cause any overheating.

I have also crawled up Nandi Hills in dense traffic and never faced the issue of overheating or car rolling back. M mode is a must in such situations and leaving the car in first gear will give good response when climbing up a hairpin bend. I didnt use the handbrake either when stopped. It is only required if your leg isnt quick enough to transition from the brake to the accelerator. Using the main brakes instead of the parking brake to do wont work well since the main brakes are powerful compared to the parking brakes, and moreover acts on the front wheels too, which are driven by the engine. This causes quick overheating of the clutch. Whereas the parking brake acts on the rear wheels and leaves the front wheel free. When the engine delivers power to the front wheels, the wheels can move to some extent as long as the suspension provides some room and by then the handbrake is released. Hence, there is a difference in these two methods of launching a car up a slope.

These AMT woes are rather scary.

Considering Maruti is selling AMT equipped top models of DZire for almost 10 lacs on road, i wonder how much value for money and peace of mind comes with it.

Would much rather go for a conventional automatic or CVT of the Ciaz or Baleno, than the Dzire AMT.

Now, I get the point. I read the manual and it was mentioned to use the parking break, though it was too late. I need to get used to that method. I didn't know both the brakes act differently on the clutch. After the trans axle warning, I used only M mode without pressing the brake with left foot; it didn't show up. Need to learn to drive an automatic.. :-)

I think we need to get used to an automatic. Unlearn a bit and learn new things -takes some time. My wife who is new to driving, drives Celerio AMT very smooth, far better than me.

Some updates from my side. I have been driving the Ignis Delta (P) AMT and this is my experience with the AMT so far:

1. Ignis seems to have some kind of a upshift limiter and the Gear will shift to a higher gear only at a minimum of 2000 rpm and not below it. However, once you have moved to the higher gear, you can continue to stay in that gear even at a lower rpm with no issues. Is this true for the other cars? I asked the NEXA folks during 1st Service if they can change it so that it can shift at 1500 rpm and they said its not recommended and they will not do it.

2. While in stop and go traffic situation, the AMT takes its time to react and is slow. If the accelerator is pressed just after releasing the brakes when vehicle is in standstill, the RPM increases and revvs without much car movement. It seems like its better for the car to slowly move using creep and then provide the accelerator input. As someone already reported, you may get honked at in stop and go traffic for being slow off the mark.

3. The first gear and second gear experience in my opinion is overall slow and requires patience. Once past these, the rest of the shifts are relatively very smooth on the Ignis.

4. The gear shifts happen at different speeds based on the accelerator input and I felt it also is somehow able to detect an incline (is it true ?) as the upshift happens later when driving on an incline as compared to flat, level surface.

The shift points are set that way to ensure that after shifting up to a higher gear, the engine will still remain in powerband and not be lugged. It is good for the engine, transmission as well as for responsive acceleration. However, the downshift points are set lower, somewhere close to 1000RPM. This will help you to remain in gear and accelerate in the same gear if the traffic speed varies quickly.

If you try to upshift before 2000 RPM, the next gear will put the car somewhere around 1200-1500 RPM which is not a band where the engine will be so responsive. This is more evident in the lower gears. Even my Celerio does not shift up both in automatic and manual modes before 2500RPM in first gear and a tad lower RPMs in higher gears. This cant be adjusted in any way.

This is a clutch learning issue. Ideally, the car should creep as soon as the brake is released. This is instant in my car. If it does not happen, then I have explained how to adapt the clutch time to time. Do this and the creep mode will become very active. Also, to enable fast creep, let go of the brake pedal quickly. If there is a slow release of the brake, the car will start rolling but the brake switch will still be in ON position since it goes to OFF only once the pedal comes back to its resting position. Hence, releasing the pedal quickly will let the TCM know you have released the brake sooner and creep will also be quick to engage.

Shift from 1-2 is annoying in my celerio also. The reason is the poor choice of gear ratio. The shift sequence by the TCM is like this: Engage clutch >> Shift to gear >> Request revv matching from ECU >> Wait for revv match confirm from ECU >> Disengage clutch

Shifting from 1-2 requires the revvs to drop to a greater extent before the 2nd gear can be engaged/clutch released. Hence, the lag in gearshift is too long. Compared to that, the rest of the ratios are closely spaced which will allow quick and smooth shifting. The 1-2 shifting can be made better by accelerating hard in first gear. That will lead to shifting at a higher RPM and the revvs drop quicker.

Gearshifts in the magnetti marelli box are based on a lot of conditions and the driving manner. Hence, the shift points also vary based on various conditions. The AMT box also calculates the incline angle based on load on the engine and delays upshift if there is an incline, which is a bliss. There are no unwanted shifts on an incline.

All of your observations (and I mean all) are similar in Tiago too. This may be because both Tata and Maruti use same AMT units manufactured by Magneti Marelli.

My colleague's new Celerio's AMT has failed on the 13th day of ownership. He was in start stop traffic and had just started accelerating when there was a sharp metallic sound and the vehicle stopped. The Maruti workshop has said that it is their first case of AMT failure which is a bit hard to believe. I have pointed my colleague to this thread on team-bhp.

That is the usual crap they come up with when you have a break down. Even in the case of my juddering issue, the initial overconfidence was such that my car was the first time they were seeing this issue and this is not common. After some interrogation, they agreed that they had just a few customers reporting this issue. Upon grilling the GM, Works manager, TSM of Maruti and so on, the matter then became a joke and they admitted that they have lost count of the number of times they have replaced clutches. The conclusion of the joke was that, you take the car N number of times to the service center complaining about clutch judder, and you get N number of new clutches. Beyond that, they cant help. :Frustrati

Leaving that apart, a breakdown is a serious matter. Can you share more details on what happened, and what was replaced? Since you say that there was a noise and then things stopped, I suspect something broke within the transmission or clutch assembly. There is nothing much mechanical within the AMT itself except for a few valves and a pair of pistons. I guess this is a Gearbox issue rather than AMT issue.

What is the Guideline to follow during Stop and Go Traffic? Should one leave the vehicle in gear or move from "D" to "N" when the vehicle is not moving in traffic.

For example if due to traffic the vehicle is in standstill and I have brake depressed in "D" mode and the vehicle is not moving. For how long is it better to stay in "D" mode before we move to "N" mode. Say would it be OK to stay that way for 15 seconds and then move to "N" or wait up to 30 secs or maybe stay that way till 1 minute? What is a good thumb rule to go by?

Also I heard that moving frequently from "D" to "N" back and forth increases clutch wear and tear - is this true? Should this be avoided?

I haven't kept time but I change to "N" from "D" if I have to stop for more than 10 secs, even at toll gates. The service advisor during my car's 1st service had informed that a couple of vehicles had to be towed from peak traffic situations due to a fried clutch as the owners kept the vehicle in "D" mode in stop and go traffic for a "long" time. I feel that MSIL hasn't made it clear to sales/service personnel at dealerships to educate the customer on this. IIRC, my sales advisor never spoke about this precaution.

I found from the service manual that a warning buzzer goes off when the clutch is on a heavy duty. Can anybody comment on this?

If it is a signal less than 60sec, you can hold the brake and leave it in gear. However, it is better to switch to neutral for the sake of safety and also to release pressure inside the clutch actuator. This though not proven, will be good in the longrun. Since the clutch actuator will not be in pressure for extended period of time. By common sense, it will be a better practice.

Repeatedly pressing brake in bumper to bumper traffic to inch forward will cause more wear on the clutch and AMT unit. But by moving from N to D frequently, unless you release the brake, clutch will still be disengaged and in pressure.

I took the car to MASS and they did a ECU reset again. The problem was partially solved but it's still jerky though greatly reduced. They don't seem to have a permanent solution to this.

The clutch of a manual usually lasts close to a lakh km of course depending on the driving. The AMT clutch giving up in under 20 K kms is strange. Add to that the engaging and disengaging is automated. That should eliminate the "Half Clutch" or "Riding the Clutch" in case of manual cars. So the clutch of an AMT should last longer.

The problem is only the AMT. Rest of the car is not a problem. Of course the quality and usual Maruti niggles are there but then we knew that before buying and made a decision to live with that. The AMT issue is the only thing I did not anticipate.