starter issue

I'm having a starter issue with my 2000 Mountaineer.

I had a remote starter installed last fall (2004). This spring the vehicle intermittenly failed to start with the key. However there was no problem starting with the remote starter.

I took it to the dealer, they replaced the transponder and programmed it to work with all three keys that I own. Of the three, the primary key would only work intermittenly (something the dealer warned me about). I suspected they didn't fix the problem...they claimed the key was defective.

A few days later the problem came back. Went back to the dealer. It sat there for a week and they were not able to replicate a sequence of events that would cause the startup to fail on a consistent basis. They claim that the remote starter system is causing the problem. However the remote starter starts the engine every time, not to mention everything worked fine for about 6 months.

Any suggestions on what's going on?
I'm going to have another Ford/Mercury dealer look at it.

It’s been my experience with various cars and trucks that once an owner has non-factory items installed to a vehicle, then all bets are off. Too often, the non-factory item will cause problems that no one but the designer of the non-factory item can diagnose. That being the case, I’ve always had a rule of thumb: Keep it stock to avoid strange problems that baffle the average mechanic. This applies to both mechanical and electrical systems.