Why does it not start after driving for about thirty minutes?

1995 CHEVROLET CAMARO

53,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC

PATRICK60392

MEMBER
2 POSTS

The car listed above is a z28 lt1, with original miles. When you first start it, it fires right off, runs great lots of power, then after 30 minutes of driving, it or just letting it come up to temperature shut it off and it just cranks over almost as if its flooded. the car has been sitting a few years, garage kept. I've replaced the fuel pump assembly and fuel filter and had injectors cleaned and one was replaced. new thermostat, low coolant sensor as well as the temperature sensor in the water pump. jumped in and it fired right up. bled the system by opening the two bleeder screws until coolant was solid stream. checked temperature it was at 195 / 200 rechecked coolant all was good. if i let it sit it will fire right up. i haven't verified if the fans were working after i replaced the coolant sensor in the water pump. i can't seem to find anyone that can answer or help with this problem, a local mechanic said Opti spark. was thinking maybe a coil breaking down after hot. i need your help on this please. thank you

Aug 9, 2022 at 5:25 PM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

Wow, nice car for sure can you upload pics? When you replaced the fuel pump and coolant sensor were they OEM parts (ACDelco)? both of these can cause what you are describing also the ignition coil can cause the issue as well. If both were OEM parts here are the instructions on how to change the ignition coil out int he diagrams below Also we should run the codes to see what comes up.

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

I noticed this has a crank driven distributor which can get wet and have problems as well. The dealer replaced these all the time. I have included the replacement instructions for this as well.

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
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Aug 10, 2022 at 9:46 AM

PATRICK60392

MEMBER
2 POSTS

Hi, thanks Ken, I’m kind of leaning on the Opti spark. I’m going to check fuel pump pressure even though it’s new a Delphi.
Then check spark; I placed rags around the bleeder screws so that coolant wouldn’t get to Opti spark. but I’m thinking it made its way to the connector etc. The coolant sensor is a Dorman. The dealer was out.
However, after I contacted you about the issue. And the engine cooled down now no start at all. It barely runs won’t take any throttle if you give it throttle it just chokes on itself and a small backfire through the intake. Sounds like it’s running on 1 cylinder. I think I ruined the Opti but it’s possible it was on its way out. The OEM Opti spark is no longer available, can you recommend a good aftermarket brand? I appreciate your help.

Images (Click to enlarge)

Aug 10, 2022 at 11:36 AM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

That is a beautiful car, nice work. Here is the part you need on Rockauto, they even have an AC Delco unit which is the one I would get. (Copy entire link)
https://www.rockauto.com/en/catalog/chevrolet,1995,camaro,5.7l+v8,1035908,ignition,distributor,7108

Please let us know what happens.

Aug 11, 2022 at 12:07 PM