I bought my Camaro at the beginning of August. Ive alwaus wanted a 3rd gen and at 17 years old when eveyone heard i boight a camaro i was the talk of my small town. It has the 305 and is a automatic. When I saw it on Craigslist I fell in love with it. Only 77k miles and he only wanted 3,000 for it. Seemed reasonable so I went and looked at it. All I can say is this guy had NO CLUE about how cars work in general. Everything was cobbed together and half a**ed. ESPECIALLY THE WIRING. So I got it for 1,800.

It ran perfect but I trailered it home and started working. Tried my best doing bondo on the few rust spots. Cleaned up the paint with some good rubbing compound. Fixed all of the lights and made sure they all worked. Cosmetically the car was beautiful. So I figured I would open my wallet and buy what it needed. ENTIRE exhaust system and new tires. That wasn't cheap.

It took me forever taking the headers that didn't fit out and putting the new stock manifolds on. I got the tires fitted and put on the car and I was ready to get it inspected.

I drove it out of the garage and figured now that I got the car 100% I would take it for a spin. I turned it off and took my shop clothes off. Came back out a minute later and it wouldn't start. It will crank and crank but won't start. I was confused abd heartbroken! I had never started it more then a few hours apart.

I came back a few hours later and it fired up. Runs perfect and purrs like a kitten. I can really give it to it and it holds steady and runs perfect. So when I start it cold the car is practically perfect.

So now I needed to find out what the problem was.

Started with spark plugs. 8 new ones. Always dry when I take them out.

Checked the coil. Good blue jumping spark and connection to distributor.

Fuel pressure is 44 when running which is perfect. Rev it and it jumps to 55 and then goes back. So that's good

Put a new cooling temp sender. Still wont start unless its cold.

Put a new ignition module in and still nothing.

New ECM. STILL NOTHING.

I can literally start it cold. Let it run for ONLY 3 SECONDS. Turn it off. Then it will crank crank crank. So I know it's not getting hot in only 3 SECONDS!

Does anyone have any other ideas?? THANKS

 

I've been having similar issues with my car, cant figure it out for the life of me. My coil ended up going and now that I have replaced it the car runs like it has a miss, and if I pull the spark plug wires on any of the 4 passenger side cylinders idle is un affected. It just doesn't make sense to me, my problem started exactly like yours though.. Good luck and keep us posted if you find anything, sorry I cant be of any help!

 

When it won't restart after running for 3 seconds, which ingredient is missing, spark of fuel?

Your fuel pressure is a bit higher than spec, but would not prevent it from starting.

 

Have you pulled the engine error codes to see if anything is amiss?

If it won't fire you are missing either fuel or spark.( or both if you are unlucky )
You say the plugs are dry which would indicate a lack of fuel?

Pressure at the rail does not equal fuel in the cylinder.The injectors may not be spraying fuel.
Start with the basics
Check injector pulse with a noid light when you have the no start problem
Check the resistance of the injectors ; hot and cold.

 

Fuel pressure regulator diaphragm leaking.

See especially at 3:16 in the vid.

 

WHICH temp sender did you replace? The single wire jobbie on the driver's cylinder that runs the gague or the two-wire jobbie at the front of the intake that tells the ECM what temp the engine is?

If it's shot (open circuit) the ECM reads that as -40*F. It'll start overnight-cold, but if it's got any fuel in the runners and temps are more typical 60-70* it'll instantly flood and not start.

Not saying this IS the problem, I'm just saying it's something to keep in mind.

Also, it might be the ECM isn't getting a reference signal from the distributor. Reads as 0 RPMs and it'll never fire the injectors. Can't say why that would be an intermittent problem, but given those symptoms, it pretty much has to be an electrical issue of some sort causing your problem. This is NOT a mechanical issue.

 

In regards to this I'd lean towards IGN module or MAF if you have one. When you get it hot to where it won't start stick your hand on an injector or two and see if they're pulsing when you crank. Or get a noid light.

The gauge sensor only makes the gauge off. He means the 2 wire sensor. You can find a chart of temperature vs resistance online and see if it acts like it's close.