Courts are not going to interfere in any policy desicions of Government, unless the violation of fundamental rights is very clearly established. In my opinion PIL will not hold any ground for this matter.
Even if we argue for the sake of this discussion, that petrol/deisel price hike is affecting common man, the continuing of subsidies by government are also no solution. If government continues to give subsidies, from where is government doing fund that loss incurred by government for providing subsidies? It resorts to printing more paper money and flushing the country with more paper money. This results in inflation and indirectly affects the common man. So prices of petrol/deisel are artificially "controlled" to fool the people on one hand, on the other hand prices of all other things keep rising, like prices of all other goods and services, food, clothing, housing etc. Subsidies are also called "indirect taxation" of people i.e. people are paying tax by inflation caused due to printing of extra paper currency by government.
A petition against the disinvestment Policy was filed in the Supreme Court by 15 Trade Unions which was dismissed by the Supreme Court on 19th November, 2002 on the ground that Disinvestment is a policy matter and the Hon’ble Court would not interfere in policy matters of the Government. In the judgment it was also pointed out that every socialist country like China had adopted the policy of economic liberalization using necessary reforms in the direction.