My 1999 Saturn SL2 starts without any trouble, but just after starting the engine drops off a bit like it wants to quit, although usually it picks right back up. The severity of the “drop off” is worse once the car is warmed up. In fact a couple of times when I’ve started it after not driving for a few days it isn’t even noticeable.
The only thing I can think of that might be causing this is the fuel pump, but I wanted to see if there were any other possibilities.
If your fuel pump keeps up with the demand of high speed highway driving, it’s pumping plenty of gas at idle. More likely your Idle Air Control (IAC).
Are you sure? From what I’ve read if the IAC were the problem, my car would be trying to stall out when ever I let the it idle at a stop, however, it’s only doing this right after I start the engine.
Of course I’m not sure. But I’m pretty sure it’s not your fuel pressure though. Hook up a fuel pressure gauge and watch it when you start the engine, your fuel pressure is probably fine.
You’re IAC may be sticking just a little at first, maybe it loosens up after that first stumble. I’d try taking it off & cleaning it.
Do you have any check engine lights on?
Nope, no warning/check lights, just the behavior.