Hard Shifting

Ok I confess I really have a 2000 Safari but the Astro forum seems to have more visitors. My Astro(Safari) has been shifting hard between all the gears and at the same time my check engine light has come on. The van has also started to hesitate when starting to accelerate from a stopped position. Any ideas, could a vacuum leak cause these issues? I don't have access to a computer code reader at this time. Thanks

Frankly, the fastest way to cut through any speculation and probably find the cause would be to scan the PCM for error codes. You can visit a local repair shop or service center, acquire a code scanner or data logger, or possibly even visit some local auto parts chain stores. I know that in my area, at least, AutoZone offers code scanning as a free service. I believe they do it as a courtesy as much as a way to sell parts (they find a suspected bad component or system, and suggest what parts might repair the problem). If you take advantage of one of those, make sure you get the actual error code numbers, and not just the "Transmission code" or "EVAP sensor code" or whatever the code desription might be. Report back with the error code number and someone here can probably point you in the right direction.