So on my 5.4l I recently ran a smoke test and discovered lots of little leaks and one big one from the intake. Tore it down and replaced upper an lower intake gaskets and the egr, as it to had a substantial leakiness. Drove around a bit and then hook the scanner up again. Before doing the gaskets my short term and long term trims were maxed.. After gaskets my MPG has come up from high 8s to about 12.5-13 mixed freeway and city(I live in. A small town).
I should also mention the i reset the data on the stored trims.
Currently my long terms are still running about 10-13% and I think the short term was 7-9% depending on how heavy my foot was. After all this I hooked up the smoke again and didn't see any indication of leaks..
There seemed to be a lot of carbon in the ports under the intake, would that be absorbing enough fuel to raise trims that much?
I'm stuck on where to go from here.. Except maybe to injectors.
Should also mention a month before this I replaced all cops and plugs, and did use motorcraft on both. Also did valve cover gaskets with intake..
I should also mention the i reset the data on the stored trims.
Currently my long terms are still running about 10-13% and I think the short term was 7-9% depending on how heavy my foot was. After all this I hooked up the smoke again and didn't see any indication of leaks..
There seemed to be a lot of carbon in the ports under the intake, would that be absorbing enough fuel to raise trims that much?
I'm stuck on where to go from here.. Except maybe to injectors.
Should also mention a month before this I replaced all cops and plugs, and did use motorcraft on both. Also did valve cover gaskets with intake..
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