I am trying to figure out which hose you guys have your water temp gauge installed in?

I know to get the most accurate, hottest readings, you would want the hose running FROM the engine to the heater core and not vice versa but, I don't know which one that is based on water flow direction.

There is a hose running from the very front of the intake to the firewall and one coming back out of the firewall right beside that one that goes to the back of the engine/intake (can't really tell), so which one is it?

 

I used the one that is attached to the metal tube that comes out of the head. The hose actually runs over the top of the valve cover and is really the only one accessable to even tap into.

The temp does not change when the heater is on full hot, so it must be the "input" hose to the core........

 

OK, well they must have changed things because both heater hoses on mine are very accessable. One comes out of the extreme front of the engine (this one comes out of the intake, not the head) and the other comes out of the extreme rear of the engine (can't see the end of it to tell if it comes out of the intake or the head)

 

Mines at the back of the engine. Didn't even know about the one up front...

 

HI!... You want to splice into the ingoing heater hose. That's the hose that comes from the intake manifold and goes to the heater core nipple that faces the driver's side of the truck. There is "NO" steel tube that comes out of the head. It comes out of the rear of the intake manifold on the 5.4 and out of the front of the 4.6's intake manifold. The steel tube coming from the rear of the engine is the outgoing line from the heater core and it goes under the intake manifold and re-enters the back of the water pump via the block under the alternator.


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Hi guys, just so you know, the 2001 and up 5.4's the heater hose comes out of the frt right of the intake manifold, not sure about 4.6's. The 2000 and older 5.4's come out the rear of the intake. The return line from the heater core back to the tube/water pump is on the rear of the engine like Neal says.

Ford changed the intake manifold design in 2001 resulting in a part plastic, part cast alum manifold.

Galaxy, since yours is a 2002, you want to put it in the hose that comes out the frt of the intake(outlet to heater core). Thats where I put mine and it works sweet.

Later

 

I see..... Mine is the oldest there is, so I guess it's not even close to how your setup is.......

All I know is I tapped into the firewall heater hose that's towards the drivers side. It's also the one that's attached to a metal tube that rises above the intake and is the one that leaks on the #4 coil if the clamp is not tight......

 

Just went and looked...The heater hose coming out of the front right side of the intake is the one that goes through the firewall on the left (drivers) side. That's the one. Thanks.

 

y wouldnt u just installt the gauge in the intake?there is a hex hed plug which can removed fairly easy using a #8

 

8 yrs later, I think hes got it.

 

Nope....I've been waiting on him to reply all this time. I would have never gotten it if he hadn't finally come along

 

Old thread! I was still in High School back then.

 

My intake doesn't have that plug..

 

I drilled and tapped a sensor into the aluminum housing just under the t-stat, about where a temp sensor would be in a normal installation. With the t-stat removed, I was able to make sure no swarf got into the cooling system. I just drained enough coolant to clear the water out of that area.