Toyota - Tacoma :: Hard Starting When Outside Air Is Hot

I've got a 1996 Tacoma - manual transmission, 4 cylinder, 2.7 liter engine with close to 170,000 miles on it - owned it for 10 years and 100,000 miles. Wonderful, great truck. Except.....

It has two starting problems and I can't seem to sort them out. The first is it's incredibly hard to start when the outside air is hot. Living in San Francisco, I usually forget about this problem until I drive to the central valley to visit my mom in August. Nothing like coming out of the rest stop, trying to start the engine and then having the feeling of doooh! again!. Seems to be worse when the outside air temp is over 85 or 90 degrees and the engine has been running than sits for 5-10 minutes. Cranks fine but won't catch. When it finally catches, it's like it's really slow to fire - can't quite explain it, but it's like it's doing a lot of thinking about actually running and has to talk itself into the idea. Can take 5-10 minutes to finally get it going, but usually 30 seconds to a minute. Always worried this'll be the time it doesn't want to go. My mechanic has looked at it a few times - but it's almost impossible to recreate in San Francisco when I get home due to the lack of warm days.

Second problem is trouble cold starting. When I come out in the morning, the engine takes two or three attempts to get it to start. Once it again, it cranks fine, but it's as if there's no fuel getting to the engine. If I just keep cranking, it won't fire but if I crank it, turn it off, crank it, turn it off and crank it again it'll always catch on the second or third go. Once the engine is at temp, it seems like less of a problem and easier starting. My mechanic say's "It's an old truck and it always starts eventually, so don't worry about it."