How to make nice gadget for my car?

Hello everybody! I've seen few threads about this, but with evolving of arduino and it's components i decided to start this thread.

I want to build or make (i'm not shure how to say it) , a module with display that can show me turbo boost pressure of my car in general and may be intake temperature for begining. May be both at same time or changing between them with a button.

I've never used Arduino, but i've read a lot and i'm ready to buy the parts and start the project. I'm thinking of some oled display + pressure sensor + Arduino platform.

My 1st question is: what set would you reccomend me ?

P.s: I need that info as Boost in BAR units and temp in Celsius units.

Does your car have sensors already for what you want to measure? If it does, you may be able to read the canbus data directly. It will make things easier.

I have had some issue with OLED displays in sunlight.

Look into reading the OBDII data for your vehicle if you have sensors. There are bluetooth adapters to access OBDII data and feed them to your Android device. Should be able to do this as well with arduino.

Well i'm thinking to use my original MAP and IAT sensor. It has 5v input voltage, which change with manifold pressures changes. I have to measure that and calculate it.

About the display i've chosen monochrome inverted red backlit 16x2. It will be easier. And may be arduino mega?

Are you going to let them remain in the system for your cars computer? If you are, you will have to watch any loading you put on them as it can affect their readings if they are not digital. If it is analog, then read the sensor output and then plug your arduino into the circuit and see if the reading changes. If the reading changes, you are putting a load on the system and it will affect your engine computer.

I still wonder if it would be better to check to see if the signals are on the OBDII buss and then read that. There are OBDII shields if I remember correctly.

I like the reverse red display.

I have Arduino MEGA 2560 and 16x2 display. Ive tryed some stuff just to ket familliar with the arduino.

Now im thinking to get signal from original MAP sensor which uses +5v and communicate with ECU. Different voltave= different pressure, which i will measure first with mechanical boost gauge and multimeter to see at what pressure - what volts i have.

Then, the main question is, how to connect this +5v to arduino and make it read the voltage, so i can program it to show pressure on the display.

I'm thinking it must be something like that:

If pinX voltage is 2,3v then lcd.print ("0,95 bar") and a lot more if and else..... ofcourse with some delays and etc.

Anyone ?

just interface with the can bus and as the fuel injection computer for the information. your dash may not show boost pressure or temp but the injection computer knows what they are. Im guessing mini copper s (if im correct then theres a app for that just plug in the Bluetooth canbus reader and use your smart phone)