vortec with occasional stumble

[big_mike]

Do you know if it's still the stock spider or the MPFI upgrade? Could be a leaking spider inside the intake, especially if pressure is bleeding off quickly. Worth checking out anyway if the pump is new and get good pressure at the port before it enters the spider.

 

[jdla140]

Maybe I missed this, but how old are the plug wires, plugs, coil, and distributor cap?