Remote start not working

The only thing I would ask....is did you wire up the second starter?

Where did you get the tach....

Try placing a working key in the ignition but don't turn it on. Then, try to remote start the car while this key is in the cylinder. If the car starts, the key in the 555u is not sending the signal to the immobilizer to allow it to crank and start. This could be due to a wiring problem with the 555u or the key in it doesn't function properly. Remove the key in the 555u and see if it will start the car the regular way or double check your 555u wiring to make sure it is getting ground on to blue wire from the alarm when you try to remote start. Also, make sure the antenna ring is securely around the edge of the key cylinder. They slip out sometimes.

If the car still fails to start, you might want to check your wiring on your starter disable relay. You must wire the large purple wire from the heavy duty satellite relay, which is the starter crank signal, to the starter side of the starter disable relay. You might have it wired to the key side of this wire. When the R/S tries to crank, it encounters the disable relay and can't crank the starter. It then shuts off and comes on to retry again without success. I have mistakenly wired a few R/S this way in the past and learned my lesson. Hope this helps.

Good advice from kevindanielk.  Another quick thing to check is the hood pin switch.  If it's grounding out, or you're testing the starter with the hood up, you would get the symptoms you describe.

-Michael