weird fuel pressure problem...any ideas???

[jwhite]

i hope this description makes sense...

background/pertinent info:
-2001 mustang
-SCT custom tune
-viper alarm

problem:
If i leave the key in the ignition (not turned on, just in the ignition) for a couple of minutes and then try to start the car, here is what happens:

-upon turning key forward, the fuel pressure gauge along with tach & speedo do a full sweep and the fuel pressure gauge remains at a pegged position...
-if i try to start the car the car WILL NOT start.

SO, i go to the trunk to see if the fuel shut off switch has been tripped, and it has not...

basically, the fuel pump is not coming on and thus the car has no fuel pressure and cannot start, but why would leaving the key in the ignition cause this?

to get the car to start, i have to wait like 5 minutes (without the key in the ignition) and she will fire right up.

Obviously the solution is to not leave my daggum keys in the ignition unless i am going to start the car, but i just thought i'd ask to see if anyone has any ideas what might be causing the fuel pump to not come on

TIA

 

[stellar591]

I would look at that alarm. Something must be shorted or not securely ground. I also have an aftermarket alarm and I had a similar problem once. The battery was disconnected for a short time and then I reconnected and the car wouldn't start. The gauges did a full sweep like you said, sometimes they would stay pegged, sometimes not. Also, the alarm was acting real funny, chirping and not responding when I clicked my key fobber. Well, we troubleshot it forever and it ended up being the buildup on my negative battery terminal causing it. Weirdest thing I've ever seen! Good luck!