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2004 express 2500 cng. 5.7L 39k mi. Limp mode after 30 - 45 seconds?

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Old March 29th, 2024, 9:51 AM
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Default 2004 express 2500 cng. 5.7L 39k mi. Limp mode after 30 - 45 seconds?

Hi , I bought a 2004 express 2500 5.7l cng with 39k on it. Ran perfect for 6 months. I started it one day, warmed it up for about a minute, started to drive it , and it went into limp mode. Got it back home, about 2 blocks. Tried to diagnose with scanner, but no power at obd port. I only see 4 wires at the back of one port. Has anyone had this problem? I need a cng wiring diagram/schematic, and some cng knowledge. The van came from Michigan, so lots of rust. Thanks for any help
Old March 29th, 2024, 5:46 PM
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dlc connector is powered by the cig fuse....check for a blown fuse.
Old April 2nd, 2024, 10:42 AM
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I did check the fuses, I will check again.
does anyone have a obd port wiring schematic? I'm trying to determine if previous owner took any wiring out to run backup camera or, who knows? Thank you for your response
Old April 2nd, 2024, 3:51 PM
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you can find schematics here:
https://charm.li/
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