Get a vacuum gauge and read THIS. THe vacuum gauge I have is also a fuel pressure gauge.

Does it rev up ok when not in gear?

 

Most of the time it revs up fine when it is in gear, I have the intake manifold off now scraping the old gaskets off and going to install the new ones.

 

Sorry on that last post I meant it revs up fine most of the time when it isn't in gear.

 

When I had the manifold off, one of the egr ports was completely plugged up with carbon so I cleaned that out, installed all the new gaskets, got the timing on, runs good now still hesitates sometimes when I accelerate, but it doesn't die like it used to when I am stopped. What could be causing the hesitation sometimes when I accelerate?

 

Now it is trying to die unless I give it gas almost constantly and it has hardly any power at all. I wonder if it could be the fuel pump?