Car Alarms: tach, remote starter, volt meter

Question
how are you doing, i dont know if you can remenber of a matrix 2005 that i did everythign is working well except the run time i mean sometimes the car turns on for 15 mins with a remote starter and sometimes it runs for 3 mins and then stops i will be better explain this to you like this sometimes when you start the car remotely the car runs for 15 mins ok but sometimes for 3 mins and it stops or sometimes for a little bit more and then it stops what could this be i think it could be the tach wire i didnt use this wire but i need your tip and if i have to connect the tach wire can you tell me where is this wire in the car because i know in the ecm has one its a black (-) but in the ecm it has a lot of black wires so it will be hard to find the right one reply to me as soon as you can thank you.

Answer
This does sound like a tach wire issue for sure. I think your unit (RS) has an adjustable sensing so you can try adjusting it for a better read and see if that works for you. Look through the install manual on how to adjust it.

How about at any engine coil. You can use any wire that is red/blue, yellow green, gray, or white. Measure the wire wire you plan on using with a volt meter set on ac you will get a reading of 2-6 volts that will increase as you step on the gas pedal while the vehicle is running.