I have a 1991 camaro with a 5 speed 355 summit racing engine, high flow holley carb, msd ignition plugs and wires and such and i just cant get my car to start after its been running for a while. From a cold start I'm good. But if I drive it for more than 10 minutes and let it sit for more than 10 minutes before i crank it again it doesn't want to start. I think its my carb because if it was my ignition system then shouldn't it be hard to crank every time? Somebody suggested that it may be my fuel pump not pumping enough fuel cause it used to have a 305 in it may be the stock pump but it seems like that would be about the same as the ignition system. I'm only 18 but i took every automotive course my highschool offered so I have a good foundation for knowledge about cars but I really don't know what the problem is this time. Any help would be appreciated.

 

let me guess, it has headers? if so, buy a heat shield for the starter and you won't have any more issues. also the 305 fuel pump, electrical or mechanical?

 

It has hooker headers. When i had my S-10 i could hear the fuel pump when I turned the key before i started the truck. With the Camaro i don't hear it. So it may be mechanical? I really don't know to be honest. I've put a fuel pump on an old chevy 1500 but I didn't know anything about it other than it was bad. I just put a new one on. I know just as much about this Camaro's fuel pump. If i thought anything on this car was made by GM other than the body then i could just look it up. But the previous owner of the vehicle thought it was a drag car so he tore it apart and rebuilt the entire car from the ground up. I've got paperwork on over $20,000 worth on parts. He knew what he was doin too so I doubt he would leave the old pump in it. I'll check the papers i have in the morning though.

 

You said "if it was my ignition system then shouldn't it be hard to crank every time? According to that, you're saying you don't have a cranking problem, but the problem is with the engine not starting (firing up). That means your problem isn't starter motor related.
So, you first need to see which kind of fuel pump you have. If a mechanical, you'll see it mounted down on the passenger side of the block, with a fuel line going in and one line out going to the carb. If it's not there, that means the factory electric in-tank fuel pump is still being used, and you need to have a pressure regulator somewhere before the carb, otherwise you'll have serious flooding problems. If a mechanical pump is there, then the electric pump has been abandoned, and since you don't hear it prime, that's a likely scenario. But, if the in-tank pump hasn't been removed and/or bypassed, the mechanical pump is going to have a heck of a time pulling fuel through the dead electric pump. When the engine goes into another no-restart mode, remove the air cleaner, look down the throat of the carb, and pump the throttle a couple of times. Do you see gas squirting? If not, you have a fuel supply issue.

 

Idk what the problem is but its goin in for an oil change a tune up and to fix my antifreeze leak. My gasket thats on the line between the engine and the radiator has blown and its been gettin progressively worse over the past couple weeks. I'll ask the mechanic tomorrow. Normally I would do that stuff myself but i can't get the plug out of the oil pan. Somebody stuck a rubber washer on the bolt and that rubber washer has swelled up over the sides of it so much you can't get a wrench on there. But I'm sure theres something I'm leaving out. Oh and i have this mysterious guage on my engine near the carb. Registers 15 psi. I'm assuming this is fuel pressure. It usually reads 7 or 8 psi if its idling.

 

That's way way the heck too high for a carb. The Holley wants between 4-7 psi, no more at any given time. Either you have an overkill mechanical fuel pump, or the electric pump is still hooked up. Look to see if there's a fuel pressure regulator under the hood. I have a feeling there may not be one, which would be your problem with that kind of pressure.

 

I took the car to the mechanic this morning. He said that i was runnin 7-8 psi with a mechanical pump and that it was appropriate to match the needs and performance of the car.

 

So at what rpm does that gauge register 15 psi as you said it did? You might want a better more accurate gauge if you like keeping an eye on your fuel pressure. For what it's worth, I had a Summit brand cheapo fuel gauge on mine (looks the same as what Autozone carries), and it started leaking on me in less than 6 months. A better name brand, liquid filled gauge would be a smarter choice imo.

 

I got the car back from the mechanic. It starts a lot more consistantly now. I just have to have the gas pedal to the floor when I try to crank it. And theres nothing wrong with that guage. The needle never goes to 15. Thats just the highest number on the guage. All he did was clean my carb. It's not perfect but at least its reliable.