probs(please help)

ok i know ive posted before but i think im just afraid to accept the fact that i need expensive engine work. well heres tha problem, i have a cracked radiator and i am working on getting that fixed and that could be part of the problem, awhile ago my car overheated and it was making this loud knocking noise like chick chick chick but only when i stopped and the oil light came on, but the weird thing is when i put it in park the oil light stays on but the noise stops and ive been told its a rod bearing prob but i really hope it isnt and if i have to get that fixed or the engine replaced how much do u think it will cost because im only in high school and i dont have much money like that so someone please help. well its more of a grinding noise and it doesnt really start until i drive my car for awhile and i have a v6 2.5l 24 valve engine
also when it makes that noise smoke will come from the muffler through the exhaust
the heat and the ac also isnt working and ive already replaced the water pump next is the radiator

ok i know ive posted before but i think im just afraid to accept the fact that i need expensive engine work. well heres tha problem, i have a cracked radiator and i am working on getting that fixed and that could be part of the problem, awhile ago my car overheated and it was making this loud knocking noise like chick chick chick but only when i stopped and the oil light came on, but the weird thing is when i put it in park the oil light stays on but the noise stops and ive been told its a rod bearing prob but i really hope it isnt and if i have to get that fixed or the engine replaced how much do u think it will cost because im only in high school and i dont have much money like that so someone please help. well its more of a grinding noise and it doesnt really start until i drive my car for awhile and i have a v6 2.5l 24 valve engine
also when it makes that noise smoke will come from the muffler through the exhaust
the heat and the ac also isnt working and ive already replaced the water pump next is the radiator
if you remove the oil filler cap does it look like it has a coating of a brown milk shake looking substance?also with the cap off turn engine on briefly and place your hand over the oil fill hole and see if you feel pressure coming out of the crank case.also when you first start the engine remove the radiator cap(with engine cold, DO NOT remove when engine is hot)are there bubbles coming out the radiator?or worse yet is coolant shooting out of it?

no there arent any bubbles or coolant coming out the radiator but it used to do that before the radiator cracked
like when it was hot coolant would come out and water too when we started the car but we changed the water pump and i dont think that helped and the engine oil cap when i take it off its like just oil on it