A few months ago I had this problem, and it was the neutral safety switch. The incident motivated me to re-wire the entire car. I've had the main parts wired together for a while now (since early June). I had zero issues. It'd start fine, the right lights would illuminate, no problem. This past weekend I was finally able to put the final pieces back in the car...seats, etc.

I noticed after I put in the left gauge cluster it wouldn't start. I unplugged it, then it started. I plugged it back in, no issues.

Tonight I took it for a cruise and noticed the temp gauge wasn't working (which I think is bc I don't have a ground wire on it.) when I got home I went under the hood to check the temp gauge connection. When I went to start it, nothing. I unhooked it and the oil pressure connection....nothing. I pulled the connection off the back of the rally cluster...nothing. B/c I have power but no spark, it reminded me of my nss incident from earlier this year. I checked the NSS, used a jumper, no spark.

Just when I think my car is good to go, it betrays me. I have no idea what it could be. I'm suspecting a short, but where is it???

Sorry for the short novel.

Any help is appreciated.

Thanks!

 

You've got no spark. You need to check whether you have current at the coil, and if not, work backward from there.

Just go one step at a time.

- Eric

 

Time to trade it in on a new car. LOL

Seriously, wiring issues can be a pain to track down. Just take your time and work your way through the problem systematically.

Good Luck

 

If you have no spark, the very first thing to do is to check for 12V at the + terminal of the coil. If not, figure out why. If you do, the problem is between the coil and the spark plug, which means coil, distributor, rotor, cap, or wires. Also, be sure to check the small wire from the points to the - terminal of the coil. This wire is often hidden and breaks may not be obvious.

FYI, in a pinch, you can run a wire from the battery to the + terminal of the coil to get you home. Note that this will not have the resistor, so if you have points the higher voltage will slightly shorten point life, but for a one-time use it's no big deal.

 

Is it cranking and no spark to start? Or is it not cranking at all?

 

I have a HEI distributor. I should've mentioned that at the top.

I have power, but when I turn the key nothing. The interior lights do dim a faintly when I turn the key, but nothing happens.

I'm backtracking in my head. I got out of the car and went straight to the engine bay. I tugged on the part of the harness the green temp wire is attached to (and ALT wires, plus oil sensor.) I hopped back in to start and nothing happened.

I'm trying to figure out if I jostled something in the engine bay, but everything is connected.

This car fires up on the first key turn every time w/o issue. Something is keeping the signal from getting to the HEI.

 

I won't be able to troubleshoot until I get home, but I'm going to start with Joe's advice. I do want to run a wire from the + terminal to the HEI just to see if it turns. I have a good feeling it will, but then what?

I'm good at connecting wires, not finding shorts.

 

So, to re-ask Eric's question...

Is it cranking and no spark to start? Or is it not cranking at all?

- Eric

 

No crank at all. I mentioned the lights dimming b/c power is going somewhere when I turn the key.

 

Check that your battery is fully charged. Then remove and clean the cables and battery terminal lugs, make sure they are shiny and tight. Make sure the junction block on your horn relay is tight. Make sure the bulkhead connectors under the power booster are plugged in tight. Then get out your meter and look for where voltage is missing if it gets that far.

 

Hmmm...Horn Relay eh? Like I said earlier I tugged on the harness and that runs near the horn relay. Maybe that's what I jostled? I'm really curious now. I wish I were home! The relay buzzes when I have the door open with the key in, but I'll give it a looksee. If that's what it is I'll be very upset with myself. I GUARANTEE it's something like that!

 

It most assuredly will be something stupid...

 

Then the problem is NOT the distributor, it's the starter circuit. First thing to check is the condition of your battery cables, specifically the attachment to the battery. I've had cables that looked good and provided good contact for low-amperage loads like dash lights, but refused to carry high current to the starter. Next, check the condition of your starter, especially the brushes and the contact disk inside the solenoid. The contact disk and the terminals it mates to arc under normal use. Eventually, the arcing damages the contact surfaces and prevents the starter from operating.

 

So I got it started, but how I got it started leads to more questions than answers.

I checked connections and ensured 12 volts was flowing and nothing was draining. Every time I troubleshooted I turned the key and nothing happened.

I watched several "no crank no start" vids on you tube. Then Joe's earlier post about jumping it from the coil became my mission. As I was trying to wedge my hand into the horrible starter location, my alligator clip hit the batt cable on the solenoid side and the ignition post simultaneously. The car briefly jolted...and scared the excrement out of me!!!!

I never could get the clip on the little post, so I gave up for the night. I turned the key one last time for good measure and it fired right up! I turned it off and on 3 more times and instant ignition. It's like nothing happened.

So the jolt must've done something. Is the starter solenoid on the fritz or do I have some other gremlins at play here?

I will go to sleep happy but perplexed.

 

Bad starter solenoid or something interrupting the flow of current through the purple wire, anywhere from the ignition switch to the starter solenoid, including the ignition switch and the neutral safety switch.

- Eric

 

I'm going to suggest you check the wiring at the starter and make sure the wiring, terminals, and connections are all serviceable, clean, and tight.

 

Solenoid will definitely get some attention, but I fear it is in the wiring. This is really upsetting too, bc it's a brand spanking new harness, but this particular problem didn't pop up until after I rewired the car.

It did fire up again this morning on a cold start (80 degrees), but if it's this touchy then I'm afraid to drive it.

 

So, it works, after bumping the starter by jumping the terminals. That means you have more voltage at the battery terminal (on the starter) than at the solenoid. Compare voltages. This may still come back to poor grounding at the dash, or possibly even at the engine. And probably a few ill connections along the way. Did you replace the terminals at the starter, and the battery cables?

 

The problem with the GM starter circuit is the long wire loop from battery to key switch to NSS to stater solenoid. Add an additional set of terminals each way through the firewall connector and you get all kinds of opportunities for increased resistance and resulting voltage drop. The GM starter solenoid is very sensitive to voltage, and all these resistances add up. If the contact disk and terminals in the solenoid itself are also pitted, that just compounds the problem. Also, if you have deleted the support strap that runs from the side of the starter up to the block, you've added resistance to the circuit. That strap not only supports the starter, it provides a ground path. Leaving it off forces the ground path to run from the steel starter body through the aluminum nose piece to the cast iron block. Galvanic corrosion between the steel starter body and aluminum nose increases resistance.

I will say that an intermittent problem as you have described is almost always the starter solenoid. That contact disk rotates in use, so sometimes the pitted areas align (resulting in no start) and sometimes they don't. I'd start with the solenoid, though while the 800 lb starter is out, you MIGHTASWELL put new brushes in it also. Be sure to install the support strap.

 

I didn't replace the battery cables. They look to be in good shape and have clean connections but we all know looks can be deceiving. The wires on the solenoid are part of the new engine chassis harness.

I have 12.64 volts at the battery, and that carries through the cable. I didn't check at the solenoid.

I'm curious about what you said about my poor grounding in the dash. Admittedly, I'm not qualified to do a complete rewire, but it was simply taking out an old harness and putting in a new harness. It's plug & play! I had no leftover pieces or wires when I did the swap. If you look at my initial post the car wouldn't start when I installed the left gauge cluster. I disconnected, jiggled the wire, reconnected and voila! It happened when I first installed the Speedo too.

I am missing a ground cable from the left cluster to the Speedo. The Speedo and the Tac have a ground wire between them. Every other wire intended for grounding is ground...there aren't many. My bad NSS issue a few months ago found that my engine block wasn't grounded. I bought the strap, but it didn't change anything noticeable.

What else should/can be grounded under the dash besides gauges and lights?

 

Interesting. That car never had a starter strap when I bought it, and frankly I didn't know it needed one. Good info! That starter and solenoid haven't been addressed since I bought it either, so who knows what their history is?

The starter is in a tight spot. Will it come out by just removing the bolts or do i have to take off the exhaust manifold? That's where I'll throw my hands up in the air!

 

It is not a grounding problem under the dash nor engine to firewall. Your main ground for the starter is the negative battery cable bolted to the block. I doubt its the solenoid contact washer because in order for that to come into play the solenoid first must energize, you are not getting that far. It seems that wiggling wires here and there are causing it to work intermittently. In addition when you accidentally jumpered the terminals at the starter it energized and turned.

 

So it's the chicken or the egg...Does wiggling wires short it out, or is the Solenoid near its end, or is it both?

Wiggling under the dash and in the engine compartment both yielded a no crank no start scenario. How on earth do I find the short?

I do think the Solenoid and starter need to be addressed. I'll start there and pray.

But what's the trick to disconnecting the solenoid wires with the starter attached??? A toddler with a wrench? Is it possible to loosen the starter with the wires attached just enough to get to the connections?

this will be fun!

 

It will slide out without exhaust component removal. Careful of the positive wire. If its tight it will tug on the battery cable guide tube at the back of the block and break it. So loosen up the cable or the tube holder. The primary (smaller) wires can be a beeoch to get off with the starter in situ. So have all the 1/4" drive tools in reach as you may have to hold the 100 lb starter with one hand and ratchet in the other. Its a juggle but not all that bad. A lift would help immensely.

Fusick part numbers:
SBS645A Starter Brace
SBS645 Heat shield
And an exhaust blanket to wrap the head pipe. Get the 2 footer and start the wrap up the pipe towards the manifold. On the other end go beyond the starter on the pipe. Your starter will be happy for many years.

Install a heavy duty truck spec soleonid. The spring is stiffer and the windings are beefier. A good starter alternator rebuild shop will be your friend here.

http://www.jegs.com/p/Thermo-Tec/The...52722/10002/-1

 

I wasn't kidding about the "800 lb" starter. It will feel like that in short order. Have a block of wood, or even your floor jack, handy to rest it on while you disconnect the wires. I like to install this Moroso quick connect harness for the next time. It clips to the solenoid.

 

Joe, that's cool! I've never seen that quick disconnect. Thanks for posting it!

 

Quick Side note - My 350 was rebuilt in Dec by McSwain Automotive in Rowlett, TX. He did a great job! I'm sure that's why the engine starts so quickly when it does catch a spark. Is it possible that's masking a failing starter/solenoid?

Thats good to know DrOldsMorland and just knowing that gives me more confidence.

That brace just goes between the 2 bolts? How can that be missing? What a simple part with a huge function!

I'll consider looking at that quick connect Joe. I think my plan of attack will be to have the floor jack under the starter and lower it oh so slightly to disconnect the wires.

 

The brace is a PITA to install, especially with headers, and frequently is left off when the starter comes out. I'll admit that I've left them off a time or two also. Unfortunately, the galvanic corrosion doesn't happen right away, so the installer isn't aware that leaving it out is a problem. In addition, some rebuilt starters don't have the correct tapped hole in the starter body for the brace to attach to anyway.



I'll also say that I've never been a fan of heat shields or insulation on the starter. The problem is that no insulation is perfect, so eventually, the temperature on both sides of the heat shield or insulation is the same. Once the starter reaches this equilibrium temperature, the heat shield or insulation holds the heat in, significantly increasing the time for the starter to cool down. If all you do is short trips, this is probably not an issue. If you ever drive the car for long periods of time, it may be a problem.

 

There's no reason a flexible ground cable can't be run in place of the brace, before installing the starter.

 

Is this how it connects? eww! That would be tough! I assumed it mounted between existing bolts when I first saw it.

 

Nope. That's not an Olds motor. The Olds starter is on the driver's side. The strap bolts to a tapped hole on the side of the starter body. The curve in the strap is to clear the solenoid. The upper end bolts to a threaded hole in the block.

 

Here are photos of the Olds starter strap in place. You can see why it gets left off.

 

[QUOTE

I'll also say that I've never been a fan of heat shields or insulation on the starter. The problem is that no insulation is perfect, so eventually, the temperature on both sides of the heat shield or insulation is the same. Once the starter reaches this equilibrium temperature, the heat shield or insulation holds the heat in, significantly increasing the time for the starter to cool down. If all you do is short trips, this is probably not an issue. If you ever drive the car for long periods of time, it may be a problem.[/QUOTE]

Yes agreed with the starter blankets. Never made any sense to wrap a starter.

 

The factory did what they had to do to keep these cars reasonably reliable and minimize warranty costs, and people drove them billions of miles without ever needing to wrap their starters.

If there's a problem with your starter you need to fix it. Don't Band-Aid it with silly solutions that cost time and money, and can cause more problems than they solve.

- Eric

 

...but a little header wrap around the tube nearly touching the starter CAN help reduce starter temps, as can ceramic coating. Ceramic coating the starter would just be silly. And pretty.

 

True enough.

- Eric

 

Check the wire going to the S terminal on the starter. It may have rubbed or melted the insulation off and the wire became grounded. Possibly it was moved when you had your hand in there and moved away from a spot where it may have been touching. Check where it may be rubbing or where there is something hot to melt the insulation.

 

Update: I replaced the starter and the solenoid. I took some sand paper to the + cable connection to the solenoid. Removal and installation isn't hard, but connecting and disconnecting the wires on the solenoid make the task a bit tedious.

All I have is a couple of jack stands and a floor jack. Once on the stands, the floor jack was a great ally in stabilizing the starter as I removed the wires.

Everything is connected and the car starts every time. There is one quirk in the start however. Sometimes it will crank, stop for a split second and then the engine will fire right up. If I kill the engine and start it up immediately after it fires right up with no pause.

I've experienced this before I had my engine rebuilt, and I thought my starter was giving out (the one I just replaced). After the rebuild it would fire with no pause in the starter. Even with all of the gremlins I've been dealing with, if the starter turned the engine fired right up.

Is the (very) brief pause between the starter cranking the engine and the engine firing up normal?

 

I don't think I've ever experienced or heard of this, but it's hard to say without hearing it in person.

Glad you got it fixed!

- Eric

 

Sounds like your timing is advanced a tiny bit too far, like its trying to kick back. The engine is causing the starter to load and the amperage must build up to compensate.