I have 2 or more websites pointing at the same IP address, does it effects the search engine rankings for each websites ? Is it bad SEO to have multiple domain names on same IP address And will this negatively impact search engine results for each ?
It's fine as long as there is only one web URL used to access a page. For example, you don't want domain1.com and domain2.com showing the same content. But if domain1.com automatically directs to domain2.com when you go to the site, that's fine.
It's also fine to have multiple domain names on the same IP address, but keep in mind that Google *will* associate them as being owned by the same person. It's only bad if one of them is doing sleezy black-hat things, that could affect the others. But if all your sites are up-and-up, then that's fine.