I have a '90 Accord that's overheating and I'm not sure why. I'm getting white smoke from under the hood - somewhere front of the fuse box but I can't tell where.
I know this isn't much to go on - how do I diagnose the issue?

I don't know much about cars but I'm a quick study, good with my hands, and not afraid to take things apart.

 

white smoke? does it smell sweet like coolant? you probably have a busted/disconnected hose somewhere. check your radiator, make sure its full then while the car is at regular temp see if you are losing coolant somewhere.

 

Very well could be a water pump issue. But look for a busted hose first. No leak, then replace the water pump.

 

The water pump is on the left (driver) end of the engine. If the smoke (water vapor/steam) is coming from the right side just in front of the under hood fuse box, more likely a hose is leaking. Pull the air intake hose off to get a better view. There is a short bypass hose, one of the heater hoses, and a few lines to the throttle body in that area. If you have a way to apply some pressure (the discharge port of a hand held vacuum pump), you should be able to pressurize the system (not too much though!) through the overflow tube. Look for a fluid leak in the area from which you see the steam. Depending on how clean you keep your engine compartment, it might help to power wash it first, then blow dry if you have a compressor (or a leaf blower works also).

 

place a piece of card board underneath your engine compartment would be a good way to find out the general area the leak is coming from.

 

Thanks everyone for the suggestions. I'll try the cardboard trick and check for leaks. I live in an apartment and park in a garage, so I don't think I can pressurize the system via a vacuum, but I'll remove the intake and check closer.