Troubleshooting stalling engine, codes p0440 and p0442

2000 PONTIAC GRAND AM

134,000 MILES • 6 CYL • 2WD • AUTOMATIC

CDANIEL95123

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The car starts up fine will idle fine, but when I go to drive it starts cutting out and stalling. Got two error codes p0440 and p0442. Has new gas cap and fuel filter also just changed. What else should I look for?

Mar 21, 2019 at 5:56 PM

SCGRANTURISMO

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Hello,

These Direct Trouble Code (DTC)s are for a big and a small leak from your vehicle's Evaporitive (EVAP) emission system. The first DTC P0440 is actually large enough of a leak to be classified as a vacuum leak. It is this one, really both are not good, but the first one that is responsible for your vehicle's drivability concern.
I have included factory troubleshooting flowcharts for both DTC's, but as you go through the first one, you will probably find both leaks. Go through these flowcharts and get back to us with what you find out.

Images (Click to enlarge)

Mar 21, 2019 at 9:55 PM