Truck randomly doesn't want to start, will later.

[fixkick]

old cars are like that, ever see any other 89s on the road now, very very rare here, 1 a month if ever, but can be repaired.
you left out the key words,
so , step 1 is do you have spark, the 1989/90s love to lose spark, due that that funky parts inside the distributor, (VR sensor + igniter)
or even a bad coil. (spark induction ignition coil)

my guess is spark is ok, but its only 5min work to test, even at the coil, with test spark plug on the end of spare spark wire.
fuel, the air horn comes off, and will start no problem with that off, so you can see fuel injectors on all 8v engines 89 to 95 (usa) and even later outside USA.
if the injector goes dead, smack the side of the fuel tank to get stuck pump in there to run
is the wires rusted behind 2door left rear tail light, g402 and pink wire?
this is an 80s car with 2 injectors so pretend 1.
https://www.youtube.com/watch?feature=pl...eHgh8#t=30

that is what injection looks like and if is dead, the pump is dead.

here is the list off all thinks that kill the 1 injector TBI dead.
1: pump dead or wires to it rusty as this car loves to do.
2: injector bad, Nah.
3: TPS sensor TP pin stick at 4vdc or more. bad TPS.
4: ignition suppressor device fell off, harness and tacho goes dead. and ECU sees tacho dead and cuts fuel until fixed.
5: CMP dead, but that kills spark and you check that first. as for sure is first first.
6: FPR regulator stuck wide open , its bad but may snap closed, if engine shakes hard enought ( i think not this) or its spring inside rusted to GONE !

best is to look for spark lost
then if that is ok, check fueling at the injector with EYES.

more, loose IG-coil fuse or its insides with hair line cracks.
more, loose FI fuse. same crack and kills fuel.
worse, bad MAIN relay ( it is main = fuel pump relay ) all in one, and can be bad. but we can diagnose to here, per above. its expensive part and non standards
and a ton of other wires to fail but we work spark the fuel first. and arrive a true cause. doing simple tests.






1989 Suzuki Sidekick 1.6/5-speed

This is driving me insane. Truck cranks and runs normally. I drive it, all works as expected. If I turn it off, sometimes it starts again, sometimes it doesn't.

Yesterday I drove it. Came home turned it off. Immediately started it again and it started normally. Turned it off, immediately tried to start again and nothing. It turns over, but never starts.

Luckily it finally did it in my driveway so I could troubleshoot the thing. Injector is pulsing gas, I have fire to the plug wires. Pulled the plugs and they look normal. Just spins with the starter doesn't even pretend to try. I messed around with it not starting checking different things until it was cool, still not starting. It isn't flooding, tried cranking with the throttle wide open. Nothing. I went inside, came out 2-3 hours later. Truck started normally again.

It has fuel and fire. What am I missing with this thing that it randomly starts or doesn't?

Thanks.