Hey guys I have a Valet remote start system on my 03 F150 It has worked great ever since I got it but I moved from Arizona to Utah and now its hit and miss if it is going to work. Somtimes it will start up and work fine but other times the truck will start and run for about 15 seconds and then shut off then it will start it up again and then shut it off and keep doing this until I shut it off with the remote or with the brake any ideas????
Just so you know the remote start is the only thing hooked up I don't have power door locks or the alarm hooked up. Just wanted the remote start for my work truck on thoes cold winter mornings Thanks for any help

 

It sounds like it doesn't know that the engine is running. Check the tach lead wire.