You still have a vacuum leak some where. I would suggest taking the intake back off and replacing all the gaskets that you did not the first time

With it running,spray around some acetylene gas from a cutting torch. Alternately propane works, but be careful with it so that it does not flash. When the gas is sucked in, things should slow down, identifying the leak. Just a wild thought from the 70's....

You can get the same effect by just spraying carb cleaner around different points of the intake, without the safety risks.
When the engine starts to slow down, you found the leak.

Alex, I have the same issue, 2004 pacifica, I removed the upper intake to check where the spark plugs are located, put it back like it was before and now, engine revs up 2 times then turns off, Did you ever figure out the issue ?

Thanks

Its been said several times in the posts if you read them

Alex, I solved the issue, get Auto-zone part number below and put it on the EGR tube top side. Reeving stopped and car runs great again.

FEL-PRO EGR Valve Gasket 72928, $2.69

https://www.autozone.com/emission-co...87486_0?review

Removal
 

think this is my problem, but the old one fell inside.... how do I remove the damn thing?

Nevermind
 

Scratch that. Oh straightened coat hook, how many times you have saved me

we just had the same problem? were you able to find it inside the intake manifold somewhow? did you have to full remove it and shake it around. we cant see it in there. and then how did you install it. there is a big round circle flat area that is connected to the tube and then the mounting flange. do you have to stretch it over the flat area then put it between the tube circle flat area and mounting flange or does it just slide over the tube? because if you just slide it over the tube then the gasket doesnt seem to actually touch anything?

i did manage to find the original gasket. hopefully the one orileys sold us is just stuck forever somewhere and not in the pistons. after finding the original it works fine, the one we put on was clearly smaller and didnt fit right so that is why we lost it. got sucked in when we started it apparently.