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Discussion Starter · #1 ·
Hi there. We bought our son a 77 Nova for his first car. It was running. We thought we would put in new spark plugs. We asked the auto parts guy what gap we should get and he said 45.

My husband took each spark plug out one at a time. Put in all plugs.

All the wires are on properly.

We were given a new coil from the friend we bought it from.

So now that he has replaced all the spark plugs and a new battery.

The car does turn over but not starting.

Like there is no spark. We thought maybe it ran out of gas even though it states we have a half a tank.

We put in a little bit of gas but not much because we have a small gas can.

Does this sound like something that happens normally and is a easy fix?

What can we do to fix this, we are not a mechanical family.

Thanks for your help
 

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I doubt the bigger gap would keep it from firing. My first thought is the "new" coil. I'd say he either reversed the wires when he installed it, broke a wire somewhere, or the new coil is bad.

Here's an easy way to check for spark. Pull a plug wire from the new plug and install one of the old plugs in the wire. lay that old plug on something bare metal in the engine bay like the exhaust manifold. Make sure the metal hex portion of the plug is touching metal. Now crank the engine and look for spark at the spark plug. You should see a nice blue spark. If you don't see spark or it looks small and yellow, check the new coil. If it has good spark, you have other issues.

I'm not sure what kind of carb your running, but on a Holley you will see gas squirt when you open the throttle. If you see fuel squirting it's not out of gas.
 

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The plug gap should be on the emission sticker on the radiator panel. Your vehicle is HEI so the gap is larger than earlier cars. I think .045"-.055" is OK on those.

My guess on your problem is the coil that was changed. If it ran before and doesn't after changing the coil then that's the first place to look.
There are two kinds of HEI coils. One has Red and Yellow wires and the other has Red and white.

You didn't say if your was a V8 or I6.
Anyway, I would put the original coil back in EXACTLY the way it came out. The parts connecting the coil to the circuit and rotor are very important.

You may need an automotive friend to help you because you may have put the coil and associated parts in wrong. You may have added an electrical "escape" path for the high voltage if you left greasy finger marks. Dielectric grease should be used on the contact spring assembly.


Also, never yank the plug wires by the wire. The core is not wire but carbon filaments that can break. You need to pull by the boots.

Plugs can pick up grease and dirt when installing if the area around the plug is not clean. Fill the gap with crud and the plug won't fire.
Good luck.
 

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Discussion Starter · #6 ·
Thank you all for your help.
I will have to check them all out when I get home.

Actually there was no coil in the car, the previous owner (a friend of ours) gave us the coil to put in. We installed it and it worked.

We then replaced the plugs, that is when the car won't start.

So fun trying to fix this car up.

Ok, will do the spark test and see how that goes.

Thanks again.
 

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When you took the old plugs out did you do them one at a time , or all at once? Double check your firing order, although even if off it should start and pop and back fire, ect. Double check your coil wire to the distributor, is it hooked up?? Also as previously stated the coil wire hook ups from the car, + to +, - to -....There are only two things that make a car run, gas and spark..if you don't have one then it's the other.:yes: pull one of those new plugs, is it wet with gas (fouled).doesn't take much...
 

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Some of the HEI ignitions were .045 and I think some were .060". Supposed to put some dielectric grease on that rubber that goes between the coil and the cap.
 
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