Electrical ? Issue. No Crank Intermittent

[Foggy]

2014 Denali. Mods in Signature. All Components in excellent shape.
On occasion after a longish drive. After Turn engine off. Wait a bit, like filling gas.
It won't start/crank. I've even put a jump box on it with no crank.
Tested Alternator (less than 6 mo old -GM unit) Tested Battery - always test excellent (less than 6 mo old)
Both positive and negative cable assemblies are less than 3 years old. Starter is actual GM starter about 3 yrs old

When this happened I had been towing for about 75 miles. All gauges and parameters were great. I'm
OCD about monitoring everything esp when towing. Ambient temp was a cool day about 80* out.

When I turn on key everything lights up normal, then when crank it's NOTHING... No click ,,, nothing.

After I jacked with it and even trying jump box starting it, nothing....
Then after about 15 minutes it cranked and ran absolutely normal.

Looking for Ideas of a possible electrical issue. Maybe an ignition switch ?? IDK
I have been paranoid to drive it anywhere since this happened, but If I run out to the driveway at any
time it will crank right up and start/run normally.
I did a battery crank test, alternator test , and a starting time test: all normal/good

 

[PG01]

2014 Denali. Mods in Signature. All Components in excellent shape.
On occasion after a longish drive. After Turn engine off. Wait a bit, like filling gas.
It won't start/crank. I've even put a jump box on it with no crank.
Tested Alternator (less than 6 mo old -GM unit) Tested Battery - always test excellent (less than 6 mo old)
Both positive and negative cable assemblies are less than 3 years old. Starter is actual GM starter about 3 yrs old

When this happened I had been towing for about 75 miles. All gauges and parameters were great. I'm
OCD about monitoring everything esp when towing. Ambient temp was a cool day about 80* out.

When I turn on key everything lights up normal, then when crank it's NOTHING... No click ,,, nothing.

After I jacked with it and even trying jump box starting it, nothing....
Then after about 15 minutes it cranked and ran absolutely normal.

Looking for Ideas of a possible electrical issue. Maybe an ignition switch ?? IDK
I have been paranoid to drive it anywhere since this happened, but If I run out to the driveway at any
time it will crank right up and start/run normally.
I did a battery crank test, alternator test , and a starting time test: all normal/good

So only happened that 1 time?

 

[strutaeng]

Starter relay? I had a no-crank once. My mechanic showed me the starter relay cover popped off. I didn't know any mechanical then, but even a quick visual would have been obvious.

Need to catch it in the act. Go down to the starter with a test light so see if starter is getting power with key switch on crank (need a helper) or use ling test leads and position test light on the dash.

 

[PG01]

Actually was thinking that… shut it off, everything heated up under hood and relay just needed to cool down…. I would replace the relays in fuse box…

 

[strutaeng]

Yep. Just swap the relays.

I suppose the starter solenoid may be going bad and won't engage after it heats up with the engine running for some time? Again, if you ARE getting power down there, that would be obvious (need to confirm with test light.) You can sometimes tap the starter while someone is bumping the key to get it to turn over. Probably a time to replace the starter in that case.

 

[Foggy]

Thanks. Yes it only happened once.. But have been afraid of being stranded so I haven't
driven it since.
I was helping a friend bring his 66 impala to the state inspection for a new title..
So we had driven about 80 miles pulling my enclosed car trailer...
Got to the inspection place... Turned off.... They told me to move to a different lane
That's when it happened. So i didn't turn it off for the next 45 minutes (idling) and then another
45 miles til had to stop for gas. It restarted at the gas station, but I let it sit for about
10-15 minutes before I even tried it. And it started. Then another 45 minutes down the road
I turned it off to unload the trailer.. It started normally then too, but it had set for about 30 minutes
there too.
I'll look into the starter relay (in the fuse box).
What else ??? Could it be the ignition switch under the steering column ????
I really shouldn't have starter heat soak as My headers are SS and ceramic coated
with plenty of clearance. And it's a real GM starter...So ??

 

[ivin74]

2014 Denali. Mods in Signature. All Components in excellent shape.
On occasion after a longish drive. After Turn engine off. Wait a bit, like filling gas.
It won't start/crank. I've even put a jump box on it with no crank.
Tested Alternator (less than 6 mo old -GM unit) Tested Battery - always test excellent (less than 6 mo old)
Both positive and negative cable assemblies are less than 3 years old. Starter is actual GM starter about 3 yrs old

When this happened I had been towing for about 75 miles. All gauges and parameters were great. I'm
OCD about monitoring everything esp when towing. Ambient temp was a cool day about 80* out.

When I turn on key everything lights up normal, then when crank it's NOTHING... No click ,,, nothing.

After I jacked with it and even trying jump box starting it, nothing....
Then after about 15 minutes it cranked and ran absolutely normal.

Looking for Ideas of a possible electrical issue. Maybe an ignition switch ?? IDK
I have been paranoid to drive it anywhere since this happened, but If I run out to the driveway at any
time it will crank right up and start/run normally.
I did a battery crank test, alternator test , and a starting time test: all normal/good

I had something similar to what you are having with my 85 Iroc Z back in my younger days. It ended up been the fuel pump. Food for though.

 

[Doubeleive]

Thanks. Yes it only happened once.. But have been afraid of being stranded so I haven't
driven it since.
I was helping a friend bring his 66 impala to the state inspection for a new title..
So we had driven about 80 miles pulling my enclosed car trailer...
Got to the inspection place... Turned off.... They told me to move to a different lane
That's when it happened. So i didn't turn it off for the next 45 minutes (idling) and then another
45 miles til had to stop for gas. It restarted at the gas station, but I let it sit for about
10-15 minutes before I even tried it. And it started. Then another 45 minutes down the road
I turned it off to unload the trailer.. It started normally then too, but it had set for about 30 minutes
there too.
I'll look into the starter relay (in the fuse box).
What else ??? Could it be the ignition switch under the steering column ????
I really shouldn't have starter heat soak as My headers are SS and ceramic coated
with plenty of clearance. And it's a real GM starter...So ??

if you suspect the starter if it happens again just pull the relay and jumper it to check operation and/or smack it with a hammer a couple times
otherwise you could look up "vapor lock" which has been a reported a few times but I think that is just a crank and no start thing, probably unrelated.

 

[Foggy]

Yeah, it's a NO CRANK issue. I replaced both the relays in the main box underhood.
One marked CRANK/START the other was marked STRTR
So I'll have to take it on a long drive that ends up back home to see if I can
duplicate the issue

 

[Doubeleive]

Yeah, it's a NO CRANK issue. I replaced both the relays in the main box underhood.
One marked CRANK/START the other was marked STRTR
So I'll have to take it on a long drive that ends up back home to see if I can
duplicate the issue

keep a meter with you and try jumpering the starter relay pins in the fuse box, if that doesn't work then check the starter cable for voltage drop.
from the battery to the starter when trying to start or when starting if it reads 10.5v or less replace the cable.
you might want to eyeball it anyway because they get burnt and/or corrode from the inside like the battery cables.