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The 2004-2008 F-150 truck was introduced in January 2003 for the 2004 model year as the redesigned eleventh generation of the F-150 lineup.

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Misfire only when hot?

Once the truck gets hot hot it starts to have misfires in 5 and 7. Misfire typically only happens at idle after coming down from higher rpm. The upstream oxygen sensors are reading 15 for long term fuel trims. This meaning that we are lean in the mixture. I have narrowed it down to possibly dirty injectors, ECU, Dirty intake valve (sealing issue).

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Was wondering if you ever got it figured out, mine is doing the exact same thing even on the same cylinders

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It turned out to be the phasers, but I don"t remember exactly. I think we got lock out phasers.

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It turned out to be the phasers, but I don"t remember exactly. I think we got lock out phasers.

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I'd say you could try to run some fuel injector cleaner through the injectors that could clean out any extra carbon build-up because if the fueling system is giving it that extra bit of pressure it could just push through the build-up but at higher RPMs, if's having trouble getting through the injector in the lower range then that would make sense. If you think it's the PCM you could get something to read what the PCM is seeing and how much it's demanding out of the injectors. I'd check battery voltage if the PCM is getting a few millivolts under what it should run the PCM could be in that sweet spot that it'll run the car and be on but at the same time be putting out a dirty signal then when you rev up the engine the alternator charges the battery and gives the PCM proper voltage. I would start with the fuel injector cleaner and check the battery voltage.

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