Okay so I've got a 94 v6 3.4l camaro. 170k miles. It has a hard time starting in the morning and after I get off work acts like it's carburated I crank it over for a good 45 second to a min before it starts then sometimes it doesn't increase in rpm if in park I have to feather the throttle up and down to get it to raise up and the exhaust fumes r awful when I do this. It seems like it's starving for fuel. But after a minute it runs fine. Then when I'm driving it will sputter like it's going to stall out if I'm under 2k rpms but if it's above 2k it's fine no sputter. And the sputter happens randomly. It doesn't do it all the time. Any ideas on either of these problems? I've replaced the fuel filter air intake cleaned the throttle body replaced idle air control sensor throttle position sensor engine temperature sensor.my mpg is awful as well. I'm lucky to get 200 miles a tank. I also just replaced the plugs last week. Any ideas?

 

When it is hard to start is it trying or does it just crank like it is out of gas? As a general rule under hard to start you have to figure out what not there. If you have compression, Air, Fuel and spark something happens. If the car does not start it will back fire unless the plugs are completely fuel fouled.

After all that your issue sounds like a fuel pump. It is a common issue and a fuel pressure test while it is acting up will tell you for sure. You most likely only have a week or so before it fails completely.

Do you hear the pump running when you first put the key on? Don't bother cranking it until you hear the pump running. You will just kill your starter. Just keep cycling the key on and off till you hear the pump.

 

Could also be a too much fuel problem. If you have leaky fuel injectors, they will "flood" the cylinders when sitting, and make the engine hard to start and run until it clears up, as in your first minute or so. That would also give you a rich smelling exhaust, which is something you're describing. Hook a fuel pressure gauge to the valve on the fuel rail and see what you have. Key on and off a couple of times to prime the system and build pressure, then turn the key off and watch the gauge. With the key off, pressure should hold, and if it drops fast you have issues with either the injectors, fuel pressure regulator, or the pump. Pressure reading should be +/- 43 psi with the vacuum hose to the regulator removed. When removing that hose btw, check for gas inside it. If there is any, the regulator is bad and needs to be replaced. After that, you can check fuel pressure with the engine running. With the vacuum hose reconnected to the regulator, your fuel pressure should be 6-8 psi lower than the first (hose disconnected) reading you got. Let us know what happens.

 

It does attempt to start and yes I can hear the pump start when ignition is on. Thanks I'll try that.