This isn't a Camaro but it's a 350 Chevy so I figure somebody on here should know. It's a 97 Silverado 1500 extended cab long bed with a 350 Vortec with about 90,000 miles. A while back I had some intake problems so the manifold had to be replaced. Now when I drive it, it will experience a hic-up, almost like a brief misfire. I've checked the seals, timing, plugs, distributor,and computer. Everything checks out fine but it's still there. I'm out of ideas and so are the mechanics I've taken it to, I'm starting to wonder if it's some sort of problem with the intake manifold itself. It will mainly occur when I'm driving 40 or over and at a constant RPM.Itusuallyoccurs every 5 to10 minutes, somedays only once or twice. Any ideas you guys could float my way would be greatly appreciated.

 

How is the fuel pressure?