[Brandon c]

I am wondering if anyone can help me out. I have a vehicle with a swapped 95-2000 Chevy 350. I believe it was from a suburban and is tbi. Here is the recent issue... When the engine is cool it will start right up. It drives great, although I don't ever really drive all that far. When I park and turn the engine off after driving far enough to have the engine warmed up and try to start after 10 min or so it will not start. It cranks strong but will not turn over. If I let it sit for an hour or more it will then start. What is the problem?

 

[Cowboytrukr]

Howdy and welcome. Let’s help you with some terminology: crank and turn over refer to the same thing. Spinning the engine over. You’re referring to it not starting.

This sounds like a failing ignition control module. If you can get it out, take it to get tested. It will take several tries to warm it up much like it would be while it’s running.

 

[Brandon c]

I just replaced the ignition control module with an AC Delco. Seems to run smoother but this issue with starting when hot is still present.

 

[Crispyt]

Could also be the coolant temp sensor having an issue. It might think that it's hotter than it really is so it's leaning out the mix too much. Or it could be the opposite, it could be thinking it's much colder than it is so it's dumping too much fuel into it. This sensor is different than the one that your gauge uses, this is the one the computer uses to make fuel trim adjustments. If you have the ability to plug into the truck with a scan tool and see what your sensors are reading I would start with that.

I would also make sure that your distributor is set correctly too.

 

[RayVoy]

Try a shot of starting fluid into the throttle body; if it starts, its a fuel problem; if it doesn't start, it's probably electrical.

 

[PlaywithTBI]

Let’s help you with some terminology: crank and turn over refer to the same thing. Spinning the engine over. You’re referring to it not starting.

Plus TBI was used from 87 - 95 then, in 96 GM went to the Vortec engine.

This sounds like a failing ignition control module.

^^^X2
What's you fuel pressure? You can borrow one from your local parts house and check.

I just replaced the ignition control module with an AC Delco.

Did you replace the ignition coil too? You can take a water bottle and spray the coil, not the wires, while idling, and see if it stumbles.

 

[Ron j]

I am wondering if anyone can help me out. I have a vehicle with a swapped 95-2000 Chevy 350. I believe it was from a suburban and is tbi. Here is the recent issue... When the engine is cool it will start right up. It drives great, although I don't ever really drive all that far. When I park and turn the engine off after driving far enough to have the engine warmed up and try to start after 10 min or so it will not start. It cranks strong but will not turn over. If I let it sit for an hour or more it will then start. What is the problem? View attachment 168452

I had the same problem a while back. It was the security sensor. This is a tiny device that is supposed to protect your vehicle from being stolen, but it just prevents you from starting it for quite some time after you drive it. I had to have mine replaced and all was well after that.