I have an 84 fiero. The problem is in it rains the engine won't turn over? In ideas what could be causing it.

Due to the removable engine grates/covers: The battery tray is susceptible to rot because the battery itself is exposed to the elements so rain washes over it and the acid rots everything beneath it. I never had this specific problem with the '87 Fiero GT that I owned, but I can see how rain water seeping in could be problematic.

Had this happen to a customers car when he went through a puddle if he shut the car off it would not crank until it dried off. Found the problem was the starter solenoid on top of the starter, the seal had cracked and every time it got wet the solenoid stopped working, replaced the solenoid with a marine application and his problem disappeared. I agree with racer on the corrosion issue, you can eliminate that problem by using "dry cell" battery, might cost a little more but no more corrosion.

is this a trick question? lordy