View Full Version : Viper 791 won't start car, sometimes

07-24-2007, 02:09 PM
Hi all, I got the Viper 791VX installed in my 06' 4Runner last month. It will start first thing in the morning without any problems. Throughout the day, especially when I'm trying to show off to somebody :) it just tries to crank over but doesn't 90% of the time. Every now and then it will start on the 2nd or 3rd time, but it is not dependable at all. Also, when it does start, about 50% of the time it will shut down and try to restart for some reason. Very frustrated with it cause it did cost a pretty penny to have it put in. Any ides what would cause this?

07-24-2007, 02:11 PM
Take it back to the place that installed it. It either sounds like there is a loose connection on the by-pass or they didnt use a tach wire and the voltage sense isnt working all the time.

07-24-2007, 05:06 PM
x2 or you can try this. get int start car with the key rev the engine to like 2-2700 rpm and press and hold the valet button till the led lights up. all that within 10 seconds of starting the car. that will relearn the tach on the car if hooked up.