High Iddle 4.9 tidbit.
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High Iddle 4.9 tidbit.
Noticed that my new to me F150 idles pretty darn fast. Normally its the idle air controller that goes on the 4.9's You can clean them or replace them. They had replaced that particular part twice with in a very short period of time. So I suspected it may be something else. ( See how good maint records helps?)
I took a can of carb cleaner and spayed it along the throttle body gasket.
Sure enough it choked it when I sprayed it along the gasket.Good thing I had one of those just sitting around.
I took a can of carb cleaner and spayed it along the throttle body gasket.
Sure enough it choked it when I sprayed it along the gasket.Good thing I had one of those just sitting around.
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From: Washington
Most of that damage probably came from the carb cleaner. There was a leak, but the gasket was probably still flat, and dusty, before the test. Carb cleaner is a potent solvent. Ford says to keep it away from critical seals, like the IMRC shaft seals. It probably turns a small leak in to a big one.
It will eat any paint it finds too.
It will eat any paint it finds too.
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Joined: Dec 2012
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Most of that damage probably came from the carb cleaner. There was a leak, but the gasket was probably still flat, and dusty, before the test. Carb cleaner is a potent solvent. Ford says to keep it away from critical seals, like the IMRC shaft seals. It probably turns a small leak in to a big one.
It will eat any paint it finds too.
It will eat any paint it finds too.
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Joined: Oct 2017
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With the way these throttle bodies suck on basically a unsupported gasket section. I may just start replacing these gaskets on all of these trucks as a normal tune up procedure.
They are cheap and takes ten minutes to swap them.
I suspect long idling periods exacerbate this issue. Both of my 4.9's were Municipal owned vehicles in their previous lives.
I bet in the winter they get turned on and run all day.
They are cheap and takes ten minutes to swap them.
I suspect long idling periods exacerbate this issue. Both of my 4.9's were Municipal owned vehicles in their previous lives.
I bet in the winter they get turned on and run all day.
Last edited by A pause for the COZ; May 12, 2018 at 09:39 AM.