remote start not working on 2000 mercury

I would start by doing as tedmond suggested. Check the bypass loop around the ignition barrel. If it's loose it could cause the intermittant issues.

Ironically, I had this same exact problem with the Design Tech unit I installed in my Jeep before installing my new Viper 5101. I always chalked it up to not having the tach wire connected. Sometimes it would crank the engine over and it would fire once or twice as if it were right on the verge of starting, then the remote car starter would stop. Often it wouldn't attempt to restart the vehicle after that.

I think what may have been happening is the Jeep would crank and as soon as the remote car starter saw a voltage increase it would back off. It was thinking the engine was running because the alternator started putting out.

I never did wire up the tach wire to see if that's what it was. Since the range was awful anyway, I upgraded to a better unit. I also wired up the tach wire on my Viper. So far I haven't had one missed start.

BTW, Prior to my Jeep I owned a 2001 Ford Taurus with a Design Tech 23927 remote car starter w/ the "key in a box" style bypass. It worked awesome and I never had any problems with it.

I'm not sure if this will help or not, but here is the link to the remote car starter I had installed in that vehicle. Troubleshooting my be the same.

http://www.designtech-intl.com/pdf/manuals/23927.pdf

1) run a tach wire

2) put the unit into voltage sense for diagnostics. If it starts, run a tach wire.

I think if you hook up the tach wire your problems will be solved.

you do not need to run a tach if you leave it in voltage sense.

just go into programming and change it.