santro crankshft failure and engine issues

I bought santro erlx on july 2007. everything went well. i was offered extended 3rd and 4th year warranty at the time of booking by susee hyundai vellore. after 2 years aroud 12000 km i had autogaz lpg retrofitment with an advanced sequential injiction plg kit after 6 months of review from various customers. i had good performance until 32000kms. on june 2010 i had a drop in pickup with ac. i was told by dealer clutch plate may be weak and needs change by dealer and hence did it for 6000rs. problem persisted. our elative told that timing pully belt may be weak. again i went to dealer and asked them to look in to that matter. after one and half days in workshop they called me to come workshop and told me that crankshaft was eroded mildly at a place where tming pully is fitted and it is an isolated problem. they told since i had fitted lpg my warranty expired. when i enquired many they said it is a unique problem occuring in many cars in santro from 40000kms to 70000kms to have such issues. if there is problem with lpg piston and engine would have problem first than crankshaft. then i  decided to service my car at chennai with warranty and asked dealer to return in running condition and they did some local work and delivered in running condition. at the time of delivery they told that they have missed my extended warranty  to register with company. i was shocked and fought with them and provided quotation and warranty registration form copy. after that i went to customer care and talked to regional office chennai. after 10 days they came down on dealer and Md of dealer agreed to repair the crankshaft under warranty saying his staff have committed mistake in failing to register warranty. now they have asked me to remove kit and i should not use it for next 13 months until warranty expires. still i have not finished repair. now after reading many articles in web i know this crank shaft fails in all santro cars but only kms vary. some as early as 18000km to 70000km. the problem starts with drop in pickup with ac and timing pully worn out with crankshaft wearing out which requires crankshaft change and engine works to some extent casting 20000 rs to 30000rs minimum in all cases. many customers are not ware of this issue before buying like me. i would give thorough detail once my repair works are over. Hyundai company sells and forgets customers. all santro owners please look for aat what km your pickup with ac drops and report to company and websites like this about their problem. we may go for replacement of engines by a legal suit on the company for selling a defective product in indian market. how to sort out this issue.

user eviewon road for many years but still crankshaft & engine issues not srted out