Chevy Nova Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
2,497 Posts
Discussion Starter #1 (Edited)
Here what I got and car tries but wont fire. I have the heavy red wire going to the big post on the starter where the pos cable hooks up. (Battery is in trunk) I have the heavy black wire going to one of the starter bolts. This is my main ground. I have a 4 pin HEI that I removed the moduel from and the condenser as requirered. I replaced with the long orange and black wires that run as a harness and pluged them into the wires harness that ran to the one side where the moduel plug into. (cap) I plugged the orange wire into the neg. side of the coil followed by the ground in the middle and the black on the pos prong on the coil. I put nothing on the prong that said battery or tac. I then connected the smaller red wire to the wire that use to run to the cap marked battery for my 12 volt swithed power. The direction said to just tape off the final white wire caused it is not used with the HEI. Whats wrong. Please help.
 

·
Registered
Joined
·
287 Posts
6al

I think that I would start by checking for power at the box. Clip your test lead to the positve stud, then probe your ground at the box. Check for your main power, then do the same for your trigger lead. Are the grounds mixed up, are they different(coil, main)? I can't remember. Check for any bare spots on the pick-up wires, this signal is very small and if grounding out will not work. Check the voltage at the box while cranking. Pull the top of the coil cap off, and check that the wires are in fact hooked-up(maybe you missed the blade??). Good luck, keep us posted.:)
 

·
Registered
Joined
·
2,497 Posts
Discussion Starter #3 (Edited)
Went back through the book and even called tec support. They expain how to test for spark by unplugging the box and putting the key in the run position and short the two wires from the box to see if I was getting spark to the plug. Because I was by myself at the time I ran a long wire from the plug to the inside of the car where the box is located. I held the wire from the plug a good inch away from ground and jumped the two wires from the box as they instructed. I was getting plenty of spark. I even had the small red lead for the ignition hook up to a direct 12 volt supply. I slip and touched the wire while testing and almost shi- myself there was so much juice. Still with all this the car fails to start. Before I hooked up the MSD the car would start as soon as I hit the key. Spent the whole day working on the car instead of enjoying the 70 degree day we had here in Michigan. Any other ideas. The tec told me if this test worked out I knew it was wired right.
 

·
Super Moderator
Joined
·
9,776 Posts
Double check the trigger polarity - the connections from the distributor to the two signal wires on the MSD box need to be hooked up in the proper way. If they're backwards, the signal pulse is the wrong polarity. At best it will trigger at the wrong spot and act like the timing is way off, or it might not trigger at all. MSD has the wiring diagrams on their website if you want to triple check those.
 

·
Registered
Joined
·
287 Posts
6al

There isn't any chance the car is flooded is there?? (try throttle wide open)Not trying to be a smart-a$$, but trying to think of anything.:)
 

·
Registered
Joined
·
2,497 Posts
Discussion Starter #6 (Edited)
I figure out the problem after sleeping on it over night. I had the main power wire running to the pos post on my starter because my battery was in the trunk. Got some 10 gage wire and ran a temp line from the box to the pos side of the battery after unhooking it from the starter post. Car fired right up. This thing had me a little upset yesterday. Thanks for all your help it got me going in the right direction.
 

·
Premium Member
Joined
·
2,354 Posts
If I remember correctly, the instructions say to run the positive wire directly to the battery. Which you did. The other thing I saw in your post, take that ground wire, and connect it to a steel surface. The starter housing is aluminum, isn't it? You can bolt it directly to the block, or a grounded terminal. Dave
 
1 - 8 of 8 Posts
Top