Is it true that modern cars can't catch on fire upon impact like older cars can?

While the probability is low, I would not say never.

Anytime you have that kind of volatile fuel on-board, the chance of having a fire is extremely high.

Most states have mandated that school bus run on diesel as it is not as volatile as gas.

The use of plastic fuel tanks and rear end collision protections have lowered the odds.

Thanks WOW, I really appreciate that.

think about this the modern cars are becoming both battery and gas now say you smash that sucker now you have two dangers battery acids and leaking gas both very explosive. all it take's is one spark BOOM plus those battery's the the hibird's are using are very powerful so now you can get shocked as well!
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HUMMMM three hazzards er danger's
oh and there toxic too that makes four