2001 Lumina 3100, excess cranking time

[talon2swords]

Was there ever a solution found to this? One of my cars does it too.

[mfewtrail]

Was there ever a solution found to this? One of my cars does it too.

Leaking injectors commonly cause this on the later 3100 model cars. Either put a fuel pressure gauge on the rail and check to see how quickly your fuel pressure bleeds off or pull a few plugs and check for wetness after the car has sit a while. If you do use a fuel pressure tester, the pressure should not drop more than 5psi in a 10 minute time period. If you do have leaking injectors and put the gas pedal to the floor when cranking the car(clear flood mode), it should fire up instantly. Release the gas pedal SOON as it fires. Also, the oil is a good indicator of this problem. It will have a strong smell of gasoline to it if they're leaking.

[tractorman]

still cranking

I removed and cleaned the IAC stepper motor and ports the other day. They really weren't that dirty, and it didn't make any difference in the symptoms.

Also while I had some stuff removed, I tightened the throttle body stop screw about 1/4 turn- thinking that is might serve a function similar to an idle screw on a carburator. Again, made no difference whatsoever.

Some here have suggested that this could be a fuel injector problem (leaking down). I don't think that's the problem- the oil never smells of fuel, and I don't get a strong fuel smell when the car is started. I've checked the fuel pressure- it comes up when the key is turned on, and it's within specs.

Neither do I think this is a spark plug problem or a mechanical problem with the engine. The plugs were removed and checked pretty recently- all in good shape, and re-gapped to specs.

The way this engine acts, it's as if it's getting no air while cranking. It's very consistent this way; if I press the gas pedal even slightly, the engine fires right up. If I don't press the pedal, I have to crank the engine significantly longer, and it will sputter a little before coming up to idle. Otherwise the engine runs very smoothly, makes normal mediocre power like any 3100 engine, gets good gas mileage, uses no oil at all.

This isn't a big deal- for a vehicle with 213,000 miles, this is a pretty minor issue. But I'd still fix the problem if I could identify it. I've entertained the idea that this could be a weak crank sensor- but I don't know why giving it a little throttle would compensate for that.

[Talontwoswords]

Someone said here or elsewhere that it may be the FPR (fuel pressure regulator).

Don't know why it would be that, unless it is malfunctioning of course. I was going to take mine off and try and ascertain if it was ok. At least it's located on top of the engine.

Will have to buy a fuel pressure gauge before I go on to the injectors.

[Azrael]

When you say you tightened the throttle stop-screw you mean you set it to hold the throttle slightly more open?

[tractorman]

Yes, about 1/4 turn. I might try tightening it further next time I have the air cleaner pipe off for some reason.

[Rhedalert]

Is the throttle body clean and free of buildup, including the small hole in the throttle plate? I figured it's been cleaned since you were already there cleaning the IAC, but I'll ask anyway.

[tractorman]

throttle plate

Hmmm... there's a small hole in the throttle plate?

Can't say that I've looked. Yes, it's clean- but I don't remember seeing a hole.

I'll have to take that air cleaner pipe off and have a look...

[talon2swords]

Ok, I put a new FPR on the car last evening. Darn thing cost 60 bucks because I didn't order it online.

I have cranked car up numerous times, and periodically during work today. It seems to be doing better and starts up on the first try. Sometimes it seems a little slow, but 9 times outta 10 it cranks right up.

We are having some cool weather here, so I guess I will know if it really worked when it warms up (if temperature has anything to do with it).