[shorod]

When's the last time you had a tune up performed on the car? Are the spark plugs and gaps good? Was the fuel filter recently replaced? Which engine does the car have? Have you checked fuel pressure, both KOEO and KOER? Any other details which could give us somewhere to start with our suggestions?

My initial guess would be a weak fuel pump, but without having any details, that's about the best I can provide.

-Rod