Hard Cold Start

[RedBird98]

I have something I just can't pin down. When starting my 98 Firebird after it has sat for some time, it takes a long time before it fires. When it is warmed up, it starts instantly.

By a long time, I mean 5-10 seconds of the starter going. I've had the car since it was a newborn. I was getting a check engine light. It was getting misfires in one cylinder (#4). I changed the plugs and plug wires. No more misfires, but still hard to start. The hard cold starting was beginning prior to the plug change...
Anyone have ideas?

[99CamaroV6]

battery/alternator?

[RedBird98]

No it cranks just fine. The engine just doesn't fire right up.

[Bass482]

I had the same problem the first time I changed my plugs. It went a way after I put my MAF Screen back in...weird Maybe that was just a coincidence...?

[RedBird98]

I haven't pulled my MAF Screen. If I get out of the car right after a cold start, it smells like it was flooded. The way it is starting is just like the old carb days when you flooded it. Once it starts I have to rev it once and then it is fine. I would think if it was a fuel pump it would do it all of the time, not just when cold starting.

[98Firebird]

mine did that today too! never really happened before... what is wrong? i just had a burnt out coil and replaced that, and put some fuel injector cleaner into it all in the last week. whats wrong?

[98Firebird]

double post... my bad

[ October 15, 2003: Message edited by: 98Firebird ]</p>

[96_fbody_sixpack]

Hmmm, my car has been doing somewhat of the same thing. but one question, if you give it gas does it seem to help ? ok, two questions, and once it fires up , did you check the exhaust for white smoke ?
If you see white smoke and the smell of rich gas, check the cylinder compression quick. could be bad oil rings , of it could be just a clogged fuel system somewhere. but a cyl check will tell ya what it might be.

[Jerriko]

The problem you are describing is usually the fuel pressure regulator or bad fuel pump seal. When you turn the car off, the regulator if working correctly, will hold fuel pressure for a long time. But if the regulator starts going away, fuel will bleed off at a quicker rate. This really doesn't hurt the car but makes it start hard after the car has sat all night. Best way to tell is to hook up a fuel pressure gauge to the schader valve with the car off. Start the car up and notice the fuel pressure. Check the specs for your engine and see if they compare. Then turn the car off, if the fuel pressure drops off at a rapid rate, you have a problem. You should not lose more than 50% of your pressure under 2 minutes. If you do loose pressure, you will them need to isolate the regulator from the tank so you can tell if the regulator or a problem in the tank is to blame. Find your fuel return line and using pliers, pinch off the rubber section of the hose. DO NOT pinch off the plastic part if your car is using plastic fuel lines. Pinching them will destroy them. That said, restart the vehicle and shut it down in 20 seconds. If the pressure drops like before, it's a leak in the tank. If it doesn't leak, its the regulator. If its the regulator, you will be able to remove the pliers and watch the pressure drop again.

[ka50]

You sure you gapped plugs right?

[RedBird98]

Thanks Jerriko...I'll give that a try.

Sixpack...yes if I give it a small amount of gas while cranking it starts quicker, and yes there is some white smoke (very small amount) I thought possibly head gasket but coolant level stays constant and temp never rises.

KA50..it was doing this prior to doing the plugs and wires. The coil packs all tested out ok...