Exclusive: Hours after India made public assurances last week that its ethanol-blended petrol was safe, the country's main auto lobby withdrew a complaint about fuel contamination it had sent to the government a week earlier. The group said some figures needed more checks. But separate communications between industry executives, reviewed by Reuters, showed that in the preceding days, top automakers Maruti Suzuki, Tata Motors and Mahindra discussed their concerns about contamination of petrol blended with 20% ethanol, called E20. The carmakers' emails show for the first time how they are privately worried about contaminants in E20, like chloride and moisture, which they say are hurting vehicles, even as they publicly back the government's rollout of the fuel