opening a Colombian bank account, you need a "Cedular"?

No

Just FYI here are some links that explain how to open a bank account as a foreigner in Colombia once you do have a cédula :

http://es.wikihow.com/abrir-una-cuenta-en-Colombiahttp://abrircuentabancariaen.com/cuenta … ombia.htmlhttp://www.notilogia.com/2016/09/como-a … antes.html

Here are links on how to get the cédula de extranjería :

http://medellinliving.com/cedula/http://migracioncolombia.gov.co/index.p … xtranjeriahttp://www.suit.gov.co/VisorSUIT/index.jsf?FI=703

Everyone seems to think so.
A banker at Bancolombia, Las Palmas, said to me, not really.
So maybe not, but I have a cedula...
BBVA might open one without.

Yes, you need a Cedula and proof that your money is earned legally.  So proof  a job, or proof of your bank account outside the country.

You can open in bbva with your passport, I've checked myself and they say yes, the rest of the banks.... don't waste your time. If you have temporal visa you can also open it, shouldn't be any problem but they ask you to many things impossible to get or at least not so easy to get specially bancolombia

Here's a question I can answer from experience!
I opened a BBVA bank account yesterday with only my US passport.
I went to the branch in Santa Fe Mall, Medellin.
It took about 1.5 hours, probably less if my Spanish was better.
I walked out with a debit card in hand.

Kudos to Karen and Steven   (in Manizales and Medellín, respectively) for finding and telling us which bank allows Expat accounts with a passport, no cédula needed.

cccmedia, from Departamento de Nariño