What part is this? Snapped off causing high idle problems
First pic looks like the cold air intake attached to rad support, that should be repaired, but won't cause high idle
Other pictures are the air pre-heater, only used when its colder out, under 45-50degF, helps warm up engine faster on Cold Start
Won't cause any running issues at all if not used or removed
So your high idle would be for another reason
Pre-heater, how it works, these have been used the same way since the 1950's, same parts
On the air cleaner there should be 2 vacuum lines, they are plugged into a thermisistor, its an unpowered valve that opens when cold
One of the vacuum lines runs to a flap valve on the air intake tube for air cleaner(not engine)
When outside air is cold enough thermisistor valve opens
When you start the engine vacuum starts to work and passes thru the valve and pulls on the valve in the air tube
The flexible tube in the pictures is on this flap valve, and this flex tube runs to a thin metal housing that is wrapped around the exhaust manifold
This is how air is pre-heated, the exhaust manifold warms up FAST, so the air inside the metal chamber heats up fast
This pre-heated air is sucked into the air filter housing instead of the colder air from behind the grill, the cold air intake, because the Flap valve diverts it
This warmer air cause engine to warm up faster, for lower emissions, but also convenience, heater in cab works sooner
As exhaust manifolds get hotter so does the air in the air filter housing and thermisistor valve closes and cuts vacuum to the flap and it also closes and you are back to the stock cold air intake operation
It is rare to even see these parts on a vehicle over 20 years old, lol, any engine work and metal housing on exhaust manifold and the flex hose just get left off on reassembly
Other pictures are the air pre-heater, only used when its colder out, under 45-50degF, helps warm up engine faster on Cold Start
Won't cause any running issues at all if not used or removed
So your high idle would be for another reason
Pre-heater, how it works, these have been used the same way since the 1950's, same parts
On the air cleaner there should be 2 vacuum lines, they are plugged into a thermisistor, its an unpowered valve that opens when cold
One of the vacuum lines runs to a flap valve on the air intake tube for air cleaner(not engine)
When outside air is cold enough thermisistor valve opens
When you start the engine vacuum starts to work and passes thru the valve and pulls on the valve in the air tube
The flexible tube in the pictures is on this flap valve, and this flex tube runs to a thin metal housing that is wrapped around the exhaust manifold
This is how air is pre-heated, the exhaust manifold warms up FAST, so the air inside the metal chamber heats up fast
This pre-heated air is sucked into the air filter housing instead of the colder air from behind the grill, the cold air intake, because the Flap valve diverts it
This warmer air cause engine to warm up faster, for lower emissions, but also convenience, heater in cab works sooner
As exhaust manifolds get hotter so does the air in the air filter housing and thermisistor valve closes and cuts vacuum to the flap and it also closes and you are back to the stock cold air intake operation
It is rare to even see these parts on a vehicle over 20 years old, lol, any engine work and metal housing on exhaust manifold and the flex hose just get left off on reassembly
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Member
Joined: Apr 2019
Posts: 6
Likes: 0
From: Philadelphia
First pic looks like the cold air intake attached to rad support, that should be repaired, but won't cause high idle
Other pictures are the air pre-heater, only used when its colder out, under 45-50degF, helps warm up engine faster on Cold Start
Won't cause any running issues at all if not used or removed
So your high idle would be for another reason
Pre-heater, how it works, these have been used the same way since the 1950's, same parts
On the air cleaner there should be 2 vacuum lines, they are plugged into a thermisistor, its an unpowered valve that opens when cold
One of the vacuum lines runs to a flap valve on the air intake tube for air cleaner(not engine)
When outside air is cold enough thermisistor valve opens
When you start the engine vacuum starts to work and passes thru the valve and pulls on the valve in the air tube
The flexible tube in the pictures is on this flap valve, and this flex tube runs to a thin metal housing that is wrapped around the exhaust manifold
This is how air is pre-heated, the exhaust manifold warms up FAST, so the air inside the metal chamber heats up fast
This pre-heated air is sucked into the air filter housing instead of the colder air from behind the grill, the cold air intake, because the Flap valve diverts it
This warmer air cause engine to warm up faster, for lower emissions, but also convenience, heater in cab works sooner
As exhaust manifolds get hotter so does the air in the air filter housing and thermisistor valve closes and cuts vacuum to the flap and it also closes and you are back to the stock cold air intake operation
It is rare to even see these parts on a vehicle over 20 years old, lol, any engine work and metal housing on exhaust manifold and the flex hose just get left off on reassembly
Other pictures are the air pre-heater, only used when its colder out, under 45-50degF, helps warm up engine faster on Cold Start
Won't cause any running issues at all if not used or removed
So your high idle would be for another reason
Pre-heater, how it works, these have been used the same way since the 1950's, same parts
On the air cleaner there should be 2 vacuum lines, they are plugged into a thermisistor, its an unpowered valve that opens when cold
One of the vacuum lines runs to a flap valve on the air intake tube for air cleaner(not engine)
When outside air is cold enough thermisistor valve opens
When you start the engine vacuum starts to work and passes thru the valve and pulls on the valve in the air tube
The flexible tube in the pictures is on this flap valve, and this flex tube runs to a thin metal housing that is wrapped around the exhaust manifold
This is how air is pre-heated, the exhaust manifold warms up FAST, so the air inside the metal chamber heats up fast
This pre-heated air is sucked into the air filter housing instead of the colder air from behind the grill, the cold air intake, because the Flap valve diverts it
This warmer air cause engine to warm up faster, for lower emissions, but also convenience, heater in cab works sooner
As exhaust manifolds get hotter so does the air in the air filter housing and thermisistor valve closes and cuts vacuum to the flap and it also closes and you are back to the stock cold air intake operation
It is rare to even see these parts on a vehicle over 20 years old, lol, any engine work and metal housing on exhaust manifold and the flex hose just get left off on reassembly
Member
Joined: Jun 2019
Posts: 397
Likes: 48
From: Fort Wayne, IN
That's just part of the flex hose portion of the "heated air" system. It's generally some sort of high-temp flexible air ducting. It's supposed to be connected to the plastic hard pipe that lays right next to the end of said clamped hose.
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