Check out this app called "Rev" i just bought for my iphone. its a little pricey once you buy the ODB cable but for me its totally worth it since i dont have a code reader...

http://devtoaster.com/products/rev/index.html

"Rev is the first and best iPhone application to connect directly with your vehicle.

Rev is an application for the iPhone and iPod Touch that monitors, displays, and records real-time vehicle data. By communicating directly with your vehicle's ECU via its OBD-II port, Rev is the first iPhone and iPod touch application to give you complete access to everything you want to know about your vehicle."

Rev gives you access to lots of vehicle metrics, communicating via an OBD-II device to extract highly accurate, real-time data directly from your vehicle's ECU. Those metrics include:

* Vehicle Speed
* RPM
* Fuel Consumption*
* Engine Coolant Temp
* Fuel Pressure
* Calculated Engine Load
* Throttle Position
* Intake Manifold Pressure
* Air Intake Temp
* Timing Advance
* Mass Air Flow
* Fuel Level
* Barometric Pressure
* EVAP System Vapor Pressure
* Fuel Trim
* Boost**

Want to know why your Check Engine light is on? Rev will tell you why!

* Engine code checking
* Listing of all engine codes thrown by the vehicle
* One-button reset of your codes and Check Engine light

My truck is basically stock but this app is sick!!!

 

Dayum I wish my provider offered those phones.

 

So you have to be in a wireless zone for it to work?

 

it uses wifi to connect to the obd2 port. kinda weird...the OBD2 wifi cable is too expensive to make it worth it...i'd rather just get a scangauge.