I have an 84 z-28 with the LG4 engine, 5 speed trans. It has a 4 barrell carb. (I think they all do) Sometimes, when its hot and I've been driving it alot, it will act sluggish and stall. It won't start right away, but if I leave it alone for about 20 minutes it will start and drive just fine. The guy who had the car before me replaced the fuel pump with an electic one. Could it be vapor lock? If so, what should I do?

 

check the ignition system,,
sounds like the pickup coil and/or ignition module

 

had a similar prob with my car but i have a mech fuel pump. Turned out my fuel line was run too close to the block and head, so the fuel was boiling in the fuel bowels.
I discovered this one day when i pulled over to show some dude my engine. When i pulled of the air cleaner i could see the fuel steaming and bubbling out the fuel bowl vents.

 

I had the same exact problem....turned out that a rubber hose leading into the fuel pump from the tank had a tear in it. The pump worked but because of the hole in the hose no fuel was able to get through. The problem only occurred when the engine was hot because the heat expanded the hole. When it was cold the hole didn't cause any problems.

Hope this helps

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92 Camaro RS, LO3, 5-spd, T-tops

Performance:
K&N Open Air Filter, Edelbrock performer TBI intake, Fastchip Prom, Timing +4 degrees, Centerforce clutch, Xact 8mm wires, SLP 1 3/4" Headers (coated), Flowmaster Catback Exhaust, Z28 Grille w/aftmkt fog lamps, MacEwen white-face guages
Electronics:
Alpine 8030 Alarm System, Valentine One Radar Detector (How did I ever drive without one?), Pioneer DEH 7450 Head Unit w/6-pack CD changer, Pioneer DEQ 7600 Sound Processor, 2 Kenwood KAC-846 Amps powering 2 12" Pro Red subs, 2 Pioneer 6x9 and 2 MTX 4x6 speakers.
NEXT UP: TBI mods, 3.42 gears w/Torsen posi

 

Thanks for the replies I think that my fuel line is run to close to my engine block. Should I reroute the line, or try to insulate it?