Volkswagen India — my vento in vw service station for the past 40 days and cause of our problem not yet tracked

Address:

Kozhikode, Kerala, 673001

My vento is in the service station for the past 40 days. The service personnel says they are unable to track the root cause.
Details of my complaint sent to customer care on 5th April is copied below.

My Volkswagen Vento KL57 G 2424 bought and serviced from Calicut phoenix showroom has been having persistent problems. It was purchased in 2013, and for the last several months, we have not had good drive with it.
We showed the service personnel the glowing 'coil' indicator and the ' engine' indicator on the dash board, but was not corrected saying there is no issue. That was almost a year back. However we noticed that there was considerable sound in the engine. We reported it several times but the service personnel returned the vehicle saying their scanner did not show any problem.
Slowly the pull of the vehicle came down considerably. We suspected injector problem, and took the vehicle to the service station but they say they dont find any issue. It is the 3rd week the vehicle is with Volkswagen Phoenix showroom Calicut. I AM NOT ABLE TO USE THE VEHICLE FOR THE LAST 3 WEEKS.

I am really disappointed with the service of Volkswagen. I cannot throw away a vehicle in just 4 years. My santro from Hyundai is working fine since 2002 and Ford Fiesta since 2007. Really sorry about this state of affairs.