Mechanics

WON'T START WHEN IT'S COLD

2003 Pontiac Grand Am • 6 cylinder 2WD Automatic • 101,000 miles

I have a 2003 grand am. Just had the fuel pump replaced and the filter as well. Now it's cold out and the car won't start. It cranks great, very strong, but it won't start. We replaced the fuel regulator, still won't start. But in putting starter fluid in the throttle, it starts right up. And now it's going to be near 40 today so it runs like a champ until freezes again. We're getting frustrated and don't know what else to look at. Please Help!
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Clyn96
December 11, 2010.



When the problem occurs, use a gage and check fuel pressure, key on, engine off. Also, key on or engine cranking, the pump receives battery voltage. Engine running, the pump receives alternator voltage, there is a difference. Do you use a block heater?

JDL
Dec 11, 2010.
Hi there.
No block heater here. We checked the fuel pressure early this morning however, and it measured in at 50#. We just checked it a good 3 hours later, car not running, and it's holding still at 40#
The other part was. In adding that starting fluid to the throttle, car started without hesitation, and continues to run.

Tiny
Clyn96
Dec 11, 2010.
No block heater here.
We did however check the fuel pressure this morning at it came in at 50lbs. In checking it a good 3 hours later, it's holding steady at 40lbs?
Otherwise, the only other thing that will get it to start and stay, is that starter fluid in the throttle. No hesitation, and very strong.

Tiny
Clyn96
Dec 11, 2010.
Did you check pressure, key on engine off, without starter fluid? If that checks out, do you have an injector pulse, engine cranking, no starter fluid.

JDL
Dec 11, 2010.
The pressure is good, and the pulse is good.

Tiny
Clyn96
Dec 11, 2010.
Doesn't make sense to me?

JDL
Dec 12, 2010.