[Rooooney]

I've been working on this problem and I have it narrowed down. I'm sucking air iaround my intake manifold. I diagnosed that per good advice on this forum by spraying the starter fluid around the area.

I replaced all of the fuel injector seals and the intake manifold gasket. It didn't work. I still get massive hesitation until my car is heated up. And I still suck air in around the same area, to right of the IM.

Could the plastic manifold be warped? If so, I really don't want to replace it. Could I use a gasket maker? Something thicker perhaps? Should I replace the bolts? Would that make a difference?

 

[300-6]

'Good old' crack/split/melt/deform/least rigid (compared to metal) plastic parts! Seeing as you managed to get at the intake manifold gasket easy enough to replace it, maybe it's time to scour your local U Pull to grab another intake manifold. Typically this won't be much of an investment aside from time and effort. Then you can carefully inspect the runners and surfaces of both manifolds for integrity against cracks and deformities and install the best one.
I haven't tangled with an Echo manifold as of yet but have replaced enough other manifolds over the years to know that maintaining gasket alignment is sometimes very difficult and that cracks and warps and such are difficult to find when the parts are not yet warmed up (materials expand when heated) by the engine.
Good luck!