Running lean code
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Running lean code
I have running lean code on 1994 Ford F-150 5.0l engine. List of new parts or replace: brake booster, fuel pressure regulator, vacuum lines in engine, check valves on secondary air injection system. Egr, vacuum solenoid's and all exhaust is tight. I'm not sure what else is there.
Cargo Master
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Check for vacuum leaks in the intake path. Between the throttle body and the heads. (i.e. Between the throttle body and plenum, between the upper plenum and lower manifold, between the manifold and heads, the EGR and IAC Gaskets, etc.)
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I have running lean code on 1994 Ford F-150 5.0l engine. List of new parts or replace: brake booster, fuel pressure regulator, vacuum lines in engine, check valves on secondary air injection system. Egr, vacuum solenoid's and all exhaust is tight. I'm not sure what else is there.
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The straight piece of air intake hose after the air filter is a little cracked at the connection but I sealed it off with duck tape.
Cargo Master
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How did you "check" them? If it's just a visual inspection, that doesn't mean a whole lot, other than verifying the gasket is there.
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Cargo Master
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When was the last time you changed the fuel filter?
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I sprayed carb cleaner around the gasket areas no change in idle
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What was the fuel pressure, and under what operating condition? Sometimes the pressure checks out at idle, but when under load and fuel consumption goes up, the pump can't keep up, and the system goes lean. Therefore I advocate checking fuel pressure under load. It can be a little tricky, but I tape the gauge to the windshield and go for a drive.
When was the last time you changed the fuel filter?
When was the last time you changed the fuel filter?
What is the normal operation psi range while driving. If it's low it's a tell sign a fuel pump problem?
Cargo Master
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Ok, so that leads me in 2 directions. A) Verify that the carb cleaner you used is actually flammable (I know, it sounds fecking stupid, but not all of it is, and I've gotten my **** bit by it before when using it to try and chase down vacuum leaks), and B) if you verify that it is, I'd start looking at fuel pressure and/or exhaust leaks.
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Ok, so that leads me in 2 directions. A) Verify that the carb cleaner you used is actually flammable (I know, it sounds fecking stupid, but not all of it is, and I've gotten my **** bit by it before when using it to try and chase down vacuum leaks), and B) if you verify that it is, I'd start looking at fuel pressure and/or exhaust leaks.
On the exhaust connection (ball and socket kind) I replaced the bolts, cleaned and sanded the rust around the connection for better seal.
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I don't recall off hand but it's running lean on bank 1. I'm not sure if it was upstream or downstream.
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I generally use some Red or UltraCopper RTV on the ball/socket connection when I hook those up. I honestly don't know if it's necessary, but it's something that I just got in the habit of doing on snowmobiles over the years, as they use a similar ball and socket exhaust connector, and they're *much* more sensitive to exhaust leaks, being 2-strokes.
