Intermittent no start - want opinions

[XH29N0G]

Several times today, (after the engine was hot), I went to start the car and there was no hit or no sound whatsoever when the key was turned. In all cases, I tightened the connections on the battery to fix it.  A few times this did not work the first time, but then it did. 

It seems to me that I have some loose connection and I think it is related to the battery.  I also think I can fix it on the run, but I am puzzled because the last time, this happened, the battery connection was already tight.

I will keep working with it, but if any have thoughts about what to check or where to check, I would appreciate hearing about them. 



On a side note, I had a nice drive today and had a chance to talk to a few people about the car when I stopped.  The car really brings in people, just to talk.

[AKcharger]

1) check/clean battery connection TO INCLUDE WIRES IN THE TERMINAL ENDS (I've found them corroded before)
2) check/clean wires at selinoid
3) check/clean wires at starter

80% chance that fixes it, if not

1) with multimeter at starter selinoid disconnect starter wire and have Helper turn key. See if you are NOT CONSISTENTLY getting 12+ volts when start is attempted, you have an ignition switch or wiring issue but I doubt it

If you ARE consistently getting start voltage it's either selinoid or starter. Swap out selinoid 1st, it's cheaper, then starter

Keep us posted

[b5blue]

I had a bad connection INSIDE the positive cable's molded battery end. Push the wire tightly into the battery connection next fail.

[XH29N0G]

Both of you,  Thanks.  This is exactly what I was hoping for - additional ideas I might not have considered.

[John_Kunkel]

Next time it happens, use any metal object and cross B and SOL terminals in the pic below. This will bypass any safety devices and energize the starter directly.

[Nacho-RT74]

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Like a screwdriver or a wrench. Some sparks could jump out, don't get scared.

[green69rt]

If none of the above work, swap in a new battery.  A weak or shorted battery can do weird things and send you down the rabbit hole.  Got another car you can swap batteries with?  it's an easy check.  Whenever I run into starting problems the first two things I check is the terminal connections/tightness and the battery condition.   Walmart will do a free battery test.

[XH29N0G]

Thanks. 

I have jumped to solenoid before, so should be all set on that.  I will check the battery as well.  My suspicion is that isn't it.  The way it behaved, was (1) no response and no buzz when the key was in and turned, (2) tightened the nut on the negative post and had it then either (a) start right up or (b) buzzing, but not enough power to start it. 

I won't get back to this until the weekend, but will update.

Thanks again to all who have responded, this will help.

[RallyeMike]

I didn't write this....  I printed it off the net and taped it to my chem cabinet. It's a good reference for when I'm not thinking clearly.
The only thing it doesn't really cover clearly is bad Starter Relay and bad Neutral Safety Switch/Unplugged Connector to Neutral Safety Switch, both of which I would check earlier rather than later.

Maybe someday I'll re-type it in a little better format.



NO START CHECKLIST

Check (more or less in this order if you can):
-battery (take it to an auto parts store and have them load-test it)
-ground wire (negative terminal-->engine block) loosen the bolt, scuff the surfaces with steel wool/scotchbrite/sandpaper, make sure there's a star-washer.
-while you have the ground wire disconnected, do the same with the connections on the starter and at the starter relay.
-re-connect the 'heavy' wires snugly. Also check the (small) ground wire at the starter relay for good conductivity.
-find, borrow, or steal a volt meter. Disconnect the yellow wire from the starter relay and jam it onto the end of the positive probe. Stick the negative probe to a good ground (if it reaches to the battery post clamp, great!) Put the meter in a position where you can see it through the windshield. Turn the key to crank, and see if you get voltage.
-whether you do have voltage or not, short the yellow-wire terminal on the starter relay to the big lug while the key is on. It should crank. If not, it's a bad starter.
-Now you've narrowed the problem down to the weakest points: The ignition switch and the bulkhead connector on the firewall, along with the yellow wire in between.

-Find the yellow wire under the dash as it comes out of the steering column, disconnect the molex connector, switch the meter to Ohms and meter between the THICK red wire and smaller yellow wire coming out of the column for continuity with the key on crank. This will check the ignition switch.
-check continuity on the yellow wire between the starter relay (keep it disconnected from the relay) and the other side of the molex connector under the dash. Put the meter on the cowl or the corner of the dashboard, the leads should reach. Put it on "beep" continuity, attach the meter leads securely to each end, and wiggle the bulkhead connector to see if the beeping gets intermittent.
-Most likely it's the bulkhead connector, but if you've verified everything else, you know it's all good. You can run and splice in a new wire through the firewall to the switch as a quick fix.

Ground the lower right terminal to bypass the Neutral Safety Switch.

[Kern Dog]

If none of the above work, swap in a new battery.  A weak or shorted battery can do weird things and send you down the rabbit hole.  Got another car you can swap batteries with?  it's an easy check.  Whenever I run into starting problems the first two things I check is the terminal connections/tightness and the battery condition.   Walmart will do a free battery test.

This makes sense.
I had an issue of intermittent slow cranking with my car. A cold start was fine. It spun over fast and fairly even for the first 10 seconds or so. Then it would slow down.
Hot restarts would be slow and rhythmic. The starter wasn't that old but I replaced it because the battery seemed to test fine with the voltage meter.
The new starter was slightly better but the main symptoms remained.
I had an AGM battery that was less than a year old but it must have had no load capability. Once a strain was put on it, it faltered. A new battery solved the problem.
I need to buy a load tester. It would help determine these problems right away.

[b5blue]

So this is a "No Cranking Over" topic not a "No Start" one. 

[XH29N0G]

Yes, intermittent no cranking over.   

I didn't get out today to try it.  I will see if it is tomorrow.  I'll keep people updated.