1999 Chevy Astro Mystery

I recently purchased the above stated van. I drove 230 miles to get it because it is a conversion van and it was hard to find with low miles. After around 145 miles the engine turned off. It started right back up but then after every 30 miles would repeat. I could hear the fuel pump humming so I drove it to the mechanic. He quoted me $800.00 to replace the fuel pump, so I did it myself. All seemed well, no humming. Drives great. Then we went on a trip. We drove 70 miles to a craft show and parked it for about 3 hours. Then we drove about 40 miles and it shut off. About every 10 miles it did the same. The next day I got in and it drove great again. The mechanic said it would have to happen to him in order for him to fix it. We are planning a huge summer trip with my two children and need to fix this problem . Please help.

Have you changed the fuel filter? A clogged or dirty filter can cause fuel pump failure, as well as cause the engine to not get enough gas. Even if that’s not the problem, a fuel filter change isn’t a bad idea anyway.

It may be a wire, or wiring connection. With the engine running, shake the wire bundles. Where you can’t reach the wires easily, or safely (near spark plug wires, exhaust, etc.), use a stick to move wires around. If the engine falters, one of those wires you moved is at fault (bare spot, broken, poor connection).
Besides wiring, there are sensors (cam, or crankshaft position, vehicle speed), ignition components (coil, etc.), which can get hot and cutout. A mechanic would know how to check these HOT.

coil,or ign module,pull codes,remove dog box time,and inspect.