After sitting for two months it will not start?

2003 DODGE DAKOTA
125,000 MILES • 3.9L • 6 CYL • 2WD • AUTOMATIC
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KEVEN IUTZI
Truck sat 2 months. Rodents filled breather box with corn. Cleaned out. Started and moved around in driveway hooking up trailer okay. Strong smell of pop corn and then burning corn. Got on road and suddenly seemed low power got 1/4 mile then stalled. Starting tries it seems to begin running roughly but never smooths out and doesn’t keep running. I’ve had water in gas before after letting vehicle sit. Drained 2 gallons through fuel manifold no water separates out. Fuel pump pressure seems good. I will check compression next though I am guessing at this point.
Oct 10, 2025 at 6:35 AM
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JACOBANDNICKOLAS
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Hi,

Have you checked the exhaust for a restriction? If you smell something burning, the converter could be partially plugged.

Remove the upstream oxygen sensor to see if it improves the vehicle's performance. If the exhaust is plugged, you will notice a difference.

Try that and let me know the results.

Take care,

Joe
Oct 10, 2025 at 7:57 PM
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KEVEN IUTZI
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upstream oxygen sensor unplugged, no difference. I did not remove it. I'm in the rust belt. I think removal will equal destruction. I did get a hold of a code reader. The only thing stored is P1494 LPD pressure Switch
Oct 11, 2025 at 5:10 PM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
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Hi:

Unplugging it won't make a difference. We need a place for the exhaust to exit. As far as the leak detection pump, that isn't going to cause it unless there is a large vacuum leak. Have you checked for vacuum hoses that have been damaged?

I attached a pic of the pump below. Check to see if anything has been chewed through, causing a leak. Also, the 3.9L is a durable engine. Unless the oil hasn't been changed or the engine was abused, compression shouldn't be an issue.

Let me know what you find.

Joe

See pic below
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Oct 13, 2025 at 9:00 PM
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STRAILER
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Please respond
Oct 14, 2025 at 12:50 PM
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