Using serial to control a remote car starter via UART

Hello, I am looking for advice on how to approach a project. I have a device that spits out serial data that does not follow any standard format. It is a remote rf receiver for a remote starter. I would like to mimic the serial data being sent to the control unit to do the lock and unlock feature of the remote starter to add a keypad to my car door. The remote starter unit also has a builtin alarm and sends the notifications to my phone which is why I must control the remote starter unit over sending analog directly to my door lock switches in my car.

Using a scope, I found the data to be coming out in pretty large packets. The first 40 bits or so are uniform with every function. There is about 720us between pulses. Because the bits do not seem to follow a standard start,bit,bit,bit,bit,bit,bit,bit,bit,stop format, the baud is unknown but some where around 1200 gauging by bit timing. But if I was to take a good guess, Id say the first chunk is the transmitter address since its the same with all the functions of my transmitter.

After much trial and error and 2 days of research, Im still having trouble finding a good angle of attack. What would you guys recommend? Is there a simple way to record that data packets and play them back to the remote starter when i want to control the functions? Or can I scope the packets and document the serial code to use the 10101 code to control a set of timers ie: if 1 writes low for 720us, else writes high for 720us?

Thanks in advance.

leckieinstalls:
I have a device that spits out serial data that does not follow any standard format. It is a remote rf receiver for a remote starter.

This seems a bit messed up to start with. Receivers don't normally spit out data - they receive it. And if there is no set format for the data it is hard to imagine how the device can work.

Also, as you say there is not a standard format I don't understand why you think a UART is relevant. They are designed for receiving or transmitting data in a very common standard format.

If your transmitter (it would be helpful if you tell us what it is) is sending regular serial data at TTL voltage levels then try receiving it with the 2nd example in Serial Input Basics. It may be useful to increase the size of the receive array from 32 bytes that I have used in the example code.

...R