I need URGENT help please!! iPhone sendind requests every 5 seconds...

Hello,

My iPhone suddenly started to send email request every 5 seconds to my server and blocking my IP because it's using a wrong (old) password in some email account I have configured.

A minute ago I talked to the guys of the hosting server I'm using and tested the following:
- Disable all email accounts: same problem
- Disable Background Actualization: same problem
- Airplane mode: fixed it...

Is there a way to find out what app (I have a lot) it's causing this?
I have my iPhone 4 with jailbreak on iOS 7.0.2

Today I received my new iPhone 6 and I would like to use it.
But I would like to keep using my iPhone 4 as well.

PLEASE help me!!!

Answers