I have a 93 z28 and lately the starter started to click about 50% of the time without cranking the engine. It started doing this a few months ago, but getting more and more frequent. Now it seems there’s about a 20% chance of getting it to start. However using jump pack has made it start first try 100% of the time. The battery was old so I figured that was the issue. And the starter was covered in gunk on the inside and outside and it’s a miracle it could work at all. So I replaced both. New starter new battery and a few headaches later and same issue, just as frequently. The first time I started the car with the new battery and starter it started second try. Ran just fine that whole night. Tried to start the following morning, nothing. Just clicks and clicks. Sometimes if I keybang it enough times it’ll crank and immediately start. Last night I tested the voltage to the starter solenoid (where the purple wire connects) while attempting to start the car and the voltage read around 6.2v. The power wire to the starter that gets constant power doesn’t drop below 11v when starting. Stays at a consistent ~12.4v when sitting. If I attempt to start the car slowly I can hear the starter relay click (click coming from the passenger side before the starter clicks) and also can hear a click from inside the steering column. It doesn’t seem to matter whether the car is in park or neutral which to me would likely eliminate the pnp switch as a problem. Wondering if a similar problem has happened to anyone else? There’s a lot more info I can share but this post is too long already so if anyone has questions I may be able to provide more important details. Thanks in advance.

 

sounds like you ignition wire is corroded or has broken wires inside the insulation. you need to check to see if it is frayed at the connector and check the resistance on the ignition wire.

 

Check voltages at the Starter Enable Relay. Relay could be bad. The schematic below will show you other places you can check voltage.

http://shbox.com/1/starter_charging_93.jpg

 

This video helped me a lot:

 

I assume you’re talking about the connector to the ignition switch? After I posted I did check that and all the pins seemed fine. The connectors looked brand new. I’m guessing the guy I bought the car from in May replaced that at some point. But after I cleaned the connections on the Trans Pos Switch and plugged it back in along with all the other parts of the starting system it has started up every time.
Turns out I have more important problems as well. Just found coolant and oil in my intake. Guessing pcv since there was no coolant when I drained the oil. But that’s a separate issue.

 

Thanks a lot! I’ll definitely use this when the engine is back together to make sure that I have good voltage on all the parts of the circuit.

 

I tested the voltages at the relay and got some weird results. The Pass Key connector pin was working correctly (tested voltage when off, on, and start) so I ruled that out. The voltage at the relay was odd. After I turned the car on I believe it was sitting at 8 volts. Then when I put it in start it went to 10 or 11. Turned it back to on and it sat at 8.5v. I thought this wasn’t supposed to happen, but unsure what it means. If I remember correctly I have tested the relay iself as well and it tested good. Connected it to a DIY circuit and it performed perfectly. The weird thing with all of this is that when I put everything back together the car has started perfectly every time since. The only thing I’m unsure about is possibly a remote start Avital system the previous owner installed. The remote start worked once and failed a few times since. But when I use the key it works every time. Hasn’t clicked once.