I have an 89 Firebird 305 TBI AT. I was having trouble with my oil pressure reading low so I went to replace the oil pressure sensor. I did drive it some with the oil pressure sensor wire disconnected from the sensor as I had to go to the store but couldn't get the wire plugged back up.

Anyways, I wasn't able to get the sensor off, the plastic part would spin around, but the metal peice wouldn't unscrew as I was using vice grips.

I plugged the connector back up, and it did have oil on it. I went to start it. It would crank but wouldn't start. I went back to check codes and noticed the check engine light doesn't come on when I turn the key to "on". The security light comes on like it should.

This has never happened before, so I'm thinking it has something to do with the oil pressure sensor. Maybe something happened when there was oil on the terminals when I tried to start it.

What is the usual cause for a no start with no check engine light?

 

Check your fuel pump relay - it is probably shot! Oil pressure switch acts as a fail safe device in case of fue pumpl relay failure. Once you remove oil pressure with a bad fuel pump relay your fuel pump will not not get power to operate. You can force fuel pump into a test mode by connecting a fused (+12) lead to Terminal (G) of the ALDL.

//RF

 

Ok, the fuse was blown by the battery. Don't know why it blew though. Could be cause I have it hot wired. The key will turn to the "on" position, but won't turn any further. So, I have some wires sticking out that when connected will supply 12v to the starter with the key turned to "on".