98 astro van starts and dies immediately. Spark OK, fuel 55 psi Fuel pump was bad, pulled it and tested it, now it starts and dies very quick. This security system is messed up cant open the passenger side door. when starting the van the security light comes on and then goes off as it should. if the security system is the problem, then how do I remedy the system. explain the 3 ten minute sessions and explain how I can open the passenger side door.

Redbeard00 could be on the right track...an aftermarket security system or a passlock bypass,( for a remote starter), would have to be reprogrammed to match any new passlock learned settings. Just experienced this myself,( previous owner had a bypass installed and I didn't know about it untill digging around in the underdash wiring looking for a convenient place to test the signal coming from the keylock tumbler. simply removing it did the trick)!!

When your theft deterrent module gives you problems.try using another key the other key could be worn. if the other key does the same thing .the dealership.will replace the theft deterrent module.with new keys.and reprogram it.its not a home fix.and it is little expensive.

It honestly sounds like a defective ignition switch. Is the security system factory or aftermarket.