PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Mis-fire when warmed up.

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Old Apr 4, 2013 | 08:26 PM
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flynbrian48's Avatar
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Default Mis-fire when warmed up.

I posted this question in the "converson" forum as well, maybe some ideas here?

'02 6.0 in my '48 Diamond T pickup. ECM reflashed by LTswap.com, VATs disabled. Starts perfectly, runs smooth and strong untill everything warms up, approx. 5-7 minutes. Then starts mis-firing, stumbles, and will ultimately die. Let it set a few minutes, seems random but doesn't need to cool completely down, then starts right up, runs good for a minute or so, then the same stumble/mis-fire issue. Temp (by aftermarket gauge) 185, I can lay my hand on the hoses/radiator/t-stat and uniformly warm.

02 sensors? ECM reprogrammed for just the upstream ones, which are in shorty headpipes off the GTO headers untill I get it toa muffler shop. New plugs, wires, fuel pump, filter. If I try to start it immediately after it dies, it fires, but won't start. Could this be a fuel filter? Injectors? It did set a couple years while I built the truck around the engie/trans.

Hoping to not have to trailer it somewhere to be scanned, but I may have to...

Brian
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