Thin pipe from bottom of the inlet manifold into the passenger compartment?

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plip1953
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Thin pipe from bottom of the inlet manifold into the passenger compartment?

Post by plip1953 »

Clearly this is some kind of vacuum pipe, but what is it it's purpose? Heater related?

Interesting the Real OEM depiction of where this pipe is attached to the manifold shows it as capped off, but mine has always had the pipe.

It came to my attention because I found that it had become detached. Could that explain the slight hunting that I've recently been experiencing during initial warm up?
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Phil
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Re: Thin pipe from bottom of the inlet manifold into the passenger compartment?

Post by hornhospital »

It draws air from in the cabin to measure the temperature. It's the thermostat that controls the heat/AC. That thermostat is a small box mounted on the under dash panel on the left side.
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plip1953
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Location: Leeds

Re: Thin pipe from bottom of the inlet manifold into the passenger compartment?

Post by plip1953 »

hornhospital wrote: Mon Jul 27, 2020 2:51 pm It draws air from in the cabin to measure the temperature. It's the thermostat that controls the heat/AC. That thermostat is a small box mounted on the under dash panel on the left side.
Thanks. If air is being drawn through the thermostat on a constant basis does that imply that the engine would run just the same whether or not the pipe is connected?

I wonder why Real OEM suggests that for my chassis number the pipe is capped at the manifold end when clearly the car has a heater and A/C?
Phil
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Re: Thin pipe from bottom of the inlet manifold into the passenger compartment?

Post by 86_6series »

IIRC on a 35B there are more ports under the IM
to connect the temp vacuum.
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